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The Jaguar XJ (1968-1992)

The Jaguar XJ (1968-1987)

Chapter 6. The Jaguar XJ (1968-1992)

By Lawrence Buja ( and Henry Fok (

  1. Overview of the Jaguar XJ6 and XJ12
  2. Specific major problem areas with Series I thru Series III XJ's
  3. Other common problem areas with Series I thru Series III XJ's
  4. Prices of XJ's
  5. Miscellaneous XJ topics
  6. Jaguar XJ quick reference

1. Overview of the Jaguar XJ6 and XJ12.

The XJ sedan was a lifesaving model for Jaguar Cars, Ltd. Since it was first unveiled in 1968, the XJ design has evolved through five generations. The first three models are differentiated only by slight styling or mechanical variations, sharing the same basic bodyshell and engine. The fourth and fifth generation XJ6's each incorporate major body, mechanical and electrical redesigns. The terminology for the different versions of the XJ6 are: Series I (1968-73), Series II (1973-79), Series III (1979-87), XJ40 (1986-94), and X300 (1995-current). The last two models share almost nothing with the earlier ones, and are rightly considered separate models and have their own sections elsewhere. The Series III, in XJ12 form, soldiered on until 1992, when it was replaced by an XJ40-based car. For more information on these seemingly conflicting dates, see "Important Note," below.

This chapter will focus on the Series I thru Series III XJ's. Due to the greater number of XJ6's, much of this section will discuss them; but everything except engine-specific information also applies to the XJ12 of the same years.

The Series I thru Series III XJ's are what many consider to be the definitive modern Jaguar sedans. The engine most commonly found in these models was the 4.2L inline 6 cylinder engine derived from the classic Jaguar XK racing motor. Other engines which were offered included the 2.8L and 3.4L inline 6 and the glorious 5.3L V12. Since the XJ was considered a luxury sedan, 90% of these cars were fitted with automatic transmissions.

"The Series 3 XJ6 looks modern enough to be perceived by the general public as an expensive, luxury vehicle. In my experience other drivers will treat you as the rich bastard they take you to be. The Series 1 XJ6 on the other hand looks older, although the only real difference to the layman is the grille. The Series 1 is the classic car. When with the Series 1 I am frequently approached by people interested in the car and old ladies will compliment me on my beautiful automobile. The Series 1 seems very much more acceptable to people, it doesn't provoke people in the same way as a car that is obviously very expensive. So, if you want to bask in the glow of admiration, drive a Series 1. If however you wish to show the proles the index finger, go for the Series 3. You think you have me pegged now? I experience dramatic swings in attitude so I have one of each" Nick Johannessen (

Build quality of the XJ varied greatly over these years, from good in the early years, to very poor during and after the British-Leyland take over in the seventies thru early eighties (approximately 1982), then back to good in the mid eighties and then very good since Ford acquired the company in 1991 until the end of Series III production in 1992. Horror stories abound:

"Over the course of the year, I spent almost $12,000 on maintenance. That's right, $12K! Mind, I took it to the Seattle area Jaguar guru (not the dealer), who charged $55 an hour for labor. I did no mechanical repairs myself (I was working 50-60 hours per week and had no time... open the bonnet and you might have no time, either!). Also, I knew from the buyers inspection that $6K or more of this was needed when I bought. None of the repairs was of a major (ie, the car died) nature. Shoulda listened..." Roger (

However, don't be put off by the horror stories, there are many great XJ's out there if you know how to find them. And once you do find a good XJ, you get a fabulous luxury car which seems to be admired by almost everyone.

"I like to think that I'm above getting caught in the pretentiousness that can come with driving a luxurious Jaguar. I've put enough sweat and blood into the dirty and ugly undersides of this car to pretty much be immune to the subtle charms of it's leather, wood and curves.
But, when pressed, I will admit to liking the attention that it can draw among the unfamiliar... To smiling when I floor it and hear the growl of the race-bred motor which I rebuilt with my own hands powering us by the staid econobox's on the highway.... To occasionally going into a corner hot, then seeing how much more I can push it before it starts to drift... To sometimes shaking my head as I look over it's glossy wood dash, leather seats and wonderful curves, wondering how this simple country boy ended up driving such a cool car... Lawrence Buja (

IMPORTANT NOTE: A common mistake is to confuse an XJ40 or X300 with an original XJ. Not surprising, since all of these cars were sold with an XJ6 badge on them.

The Series III was originally intended as a stop-gap model; something to keep the wolves from the door while the replacement for the original (then 10-year-old design) was designed and built. However, it ended up becoming the most numerous of the three series because the design, code-named "XJ40" and begun in the 70's, was repeatedly delayed. When the XJ40 (badged as an "XJ6" finally appeared after a (reportedly) 14 year gestation, it replaced the Series III slowly; introduced in Europe in 1986, it was produced alongside Series III cars for the US market until 1987, when the original XJ6 was killed off. By this time, Jaguar had more or less perfected the design of the XJ, and was well on the way to having a reputation as a builder of reliable, refined, and interesting luxury sporting sedans after the quality debacle from the late 70's under the British Leyland conglomerate until 1981-82 (just after Jaguar left the conglomerate).

Due to some disturbing proposals by Jaguar's former parent corporation, British Leyland, the XJ40 was deliberately designed so as to be unable to have a V-configuration engine of any sort. The engine bay was specifically designed for a slant six; in preventing the installation of the Rover V8 truck engine, the designers denied Jaguar a V12 variant of the XJ40. In order to not lose sales, Jaguar continued to build Series III XJ12's on almost a one-off basis until the redesigned XJ40 engine bay made it into production in 1993. Since the United States did not receive any XJ12's during the Series III run due to government regulations, many Americans are unaware of the continuance of the line until 1992. Likewise, many other markets are unaware that the original XJ6 made it into 1987 before being killed off. Of course, these staggered dates of production tend to confuse people when discussing their cars.

The XJ40 was a clean-sheet design, sharing almost nothing with it's predecessor. It was designed to look like a Jaguar, while being much easier and cheaper for the (then) struggling company to make. It was a roomy design, but there was much debate about the largely boxy look of the new sedan. Many thought that it wasn't as distinctive as a Jaguar sedan should be, while others liked it. The XJ40 was also powered by a new family of engines initially, the AJ6 and later the AJ16 slant-six engines, in displacements from 2.9L to 4.0L; the later, XJ12 versions received a revised 6.0L version of the mighty Jaguar 5.3L V12.

Unfortunately, the XJ40 suffered from quality control and design problems its first few years (86-90, especially) and did much to damage the reputation of Jaguar. Door handles breaking off, self-levelling suspension that didn't, computers that reported non-existent problems, and fragile interior trim put many people off. Eventually all these problems were corrected, but the damage was done. Jaguar fell on hard times and was bought out by Ford in 1990.

However, even before the Ford buy-out, forces of renewal were on the move at Coventry. The replacement for the boxy-looking XJ40 was on the drawing boards, and the project, named X300, bore a familiar-looking face; that of the Series III! The X300 was a restyle of the XJ40 to look like the Series III in an effort to increase sales. In addition, many of the XJ40's trouble areas were redesigned or eliminated. This car replaced the XJ40, worldwide, in 1995, with an XJ6 and an XJ12 version (and the same engines as it's predecessor). Both of these were scrapped when the Jaguar AJ-V8, an engine design also in progress since before the buy-out, made it into production in the 1998 models as the XJ8. As of this writing, July of 2001, it is the current model bearing the "XJ" series name. There is a rumor that this car is slated to be replaced in 2003 with a Ford-corporate-platform badge-engineered model, but only time will tell...

The final run of the original XJ, the Series III, had indifferent build quality from 1979 until 1982. Jaguar "cleaned house" in 1982, and starting in that year, there were quantum strides made in build quality, as well as individual component longevity. Quality of the Series III never declined after that point; by 1984, most mechanical problems had been solved. By 1986, with the improvement in the paint process, there simply weren't many problems with the cars - they were more or less perfected, leading to the odd situation that the car that "replaced" the XJ6 was not as "good" a car. This guide is intended to introduce you to the original Jaguar XJ, tell you a little about their history, outline some of their weak points and give you some tips on how to avoid buying a bad XJ.

Please remember that since this guide presents a critical look at known problem areas in Jaguar XJ's, it gives the appearance that all XJ's suffer from horrendous numbers of problems. This is not the case, a well-maintained XJ will be free of most, if not all, of the defects described here. The goal is to document what might go wrong so that you can distinguish a great XJ from a poor one.

First, a little background on the evolution of the XJ line:

In 1968, Sir William Lyons, founder of Jaguar, unveiled his final sedan design to the world, the XJ6. The Series I thru Series III XJ's are what many consider to be the definitive modern Jaguar sedans. The engine most commonly found in these models was the twin overhead cam 4.2L inline 6 cylinder engine derived from the classic Jaguar XK racing motor. Other engines which were offered included the 2.8L and 3.4L inline 6 and the glorious 5.3L V12.

"Not many cars cause as much of a stir on their introduction as did Jaguar's XJ6 in 1968. Designed to replace not only the large Mk.X-derived 420G saloons, but also the compact Mk.2s and the midrange S-types and 420s, they had a formidable task ahead of them. Yet they were every bit up to what their makers expected of them, and over the next decade, the XJ6 became an acknowledged automotive standard for refinement and luxury.

"There were perhaps two flaws in the original 1968 range: lack of room in the rear and an engine (the 2.8 litre) which acquired an unfortunate reputation. To provide more room, the long-wheelbase XJ6L was announced in 1972, and that longer wheelbase became standard on the Series 2 cars a year after their 1973 introduction. The 2.8 litre engine disappeared from the range, and was replaced from 1975 by a 3.4 litre derivative of the standard 4.2 litre type. Meanwhile the short-wheelbase car resurfaced in 1973 with striking two-door coupé bodywork as an XJ6C.

"It was unfortunate for the Series 2 cars that they should have had to live through that period in the middle and late 1970's when Jaguar's very existence was under threat. Under British Leyland, Jaguar were lumped together with Rover and Triumph in an unhappy amalgamation which did nothing for the morale of their workforce. Quality suffered - often rather publicly.

"As a result, there are good and bad results of these [Series 2] cars to be had today. The enthusiast who picks a bad one will regret it bitterly, but the buyer who finds a good XJ6 of any vintage will derive enormous satisfaction from it." James Taylor, Brookland Books, Jaguar XJ6 Gold Portfolio.

THE SERIES I XJ6 (1968-1972): If you are specifically interested in the classic Jaguar Saloon styling, consider the Series I XJ6's (1968-1972). The Series I's also do the best job of combining the elements of traditional Jaguar saloon design with modern road handling adaptations. The cockpit is very traditional Jaguar with large E-type switchgear.

"The car is a delightfully luxurious carriage, with the knack of travelling fast without disturbing the passengers. The flat ride permits fast cornering and fierce braking with no risk of pitching the occupants on top of each other. Because of its really exceptional roadholding and light steering, this big car feels like a small two-seater to drive." Autosport, September 27, 1968.

However, some aspects of this car such as the carburetion, the early model gearbox and the age of these cars makes them poor candidates for daily drivers.

"I'd make my vote for the Series I XJ6 (ok, I'm a little prejudiced because I own one, but I still think it's the best and purest expression of the final Lyons design). It was just as he thought it should look (before federal regulations mandated so many changes that the pure design look was gone. It was the only XJ6 version with all-chrome bumpers and truly operational wing windows. The winged adornment on the trunk was a vintage Lyons' touch and it's a shame practicality won out on the Series II and beyond as the lovely wings were replaced by a clunky light fixture." Craig Burlingame (

THE SERIES II XJ (1972-1979): The SII XJ was only cosmetically different from the SI XJ. The front bumpers were raised to a standard height and the front grill was much smaller, with horizontal bars. SII XJ6's delivered to the US were fitted with large (some say unsightly) black rubber bumpers to satisfy US safety standards. The dashboard was updated to a more modern layout.

"Heeding their critics, Jaguar cured that with the Series Two, and the car is now very good in these areas. Set neatly into the wooden dash, the tacho and speedo form the centre of the instrument grouping with fuel and water, oil pressure and volts ranged on each side of them. All six dials are easily visible and read, having white markings on black faces. A series of tell-tales should something fail, is arranged in strip between the tachometer and speedo. The ignition switch is in the lower dashboard edge to the right of the steering column and the lights switch to the left of it. Both have their various markings illuminated at night by the fibre-optic cable that feeds the light from a central source. Steering column stalks now control the dipping of the lights and turn indicators, and the washing and wiping of the windscreen...

"...Four push-push switches are arranged across the the top of the centre console to look after the map light, interior light, heated rear window, and switchover for the twin fuel tanks (each holding 10 gallons). All four are color-keyed at night to make identification as easy as possible. Then there's the gearlever, which is well-enough located, and after it comes the switch for the central locking system, and the five for the power windows (one is a lock to stop children working them)." Car, August 1974.

Early SII's shared the same short 108.9 inch wheel base. In 1972 the wheelbase was extended 4 inches (to 112.8) to create the long wheel base model known as the XJ6L. Both 6 and 12 cylinder models were available. During this period, British-Leyland took control of the company which led to the worker morale and build quality plummeting. Very late models had an early form of the fuel injection system on the Series III.

Conventional wisdom is to avoid Series II XJ's due to severe quality control problems. Specifically avoid those built during and just after the British Leyland years (1973-1980). However, many of the problems with these model should have been corrected by now through regular maintenance over the years.

"Series I XJ6's are desirable IMHO because the front end treatment and dash are different, giving it sort of a transitional old-world charm -- half way between a Mark II and the later XJ6's. They also have a manual choke which is a big win. I would avoid series 2 carbureted cars like the plague (they just cannot run well). Early Series II XJ6's have the same carb's as Series I's (dual Strombergs), but have a wretched water-based automatic choke. These never work and cannot be fixed." Joseph Augenbraun (

"On the other hand, we judge that there still is no car which offers quite such a combination of silence, effortlessness, soft ride and speed for the money. You have to judge for yourself whether the high costs are worth it to you - bearing in mind that a Benz or a BM[W] or even a Cit[röen] aren't cheap to run or service either." Wheels, March 1978.

"... I see no reason why Jaguar shouldn't continue to build the XJ for another ten years. This sort of charm will never be obsolete." Patrick Bedard, Car and Driver, December 1978.

The XJ6 Coupe (1975-1977): The one Series II XJ which has become very collectable is the XJ Coupe, a low production, two door sedan. Sold for only three years starting in 1975, they were based on the short wheelbase XJ platform and came with either 6 and 12 cylinder engines. These were the first production Jaguars to be fuel injected. An aborted attempt was made to field a XJ12C racing team, but the extremely fast cars were plagued with mechanical problems. While beautiful, finding replacement glass and body panels can be a problem.

"If you like the XJ6 but it's just too big, there is the XJ6C two door coupe. I bought one of these a while back after falling in love with my brother's '6, but alas it had terminal radius arm mounting point problems. This was a car that "just felt right". The LWB XJ6 really is a big car, and the coupe feels a lot smaller somehow. And if the 4 door XJ6 is beautiful, the coupe is a knockout. I've yet to see a picture that does its flowing lines justice." Paul Dodd (

"A reliable Jaguar XJ6C is one of the world's very best cars. It will be a long time before somebody builds a car we'll all be able to step out of and know is significantly better in ride, handling, sound insulation and comfort than the Jag. It'll be five years, maybe 10, and when it happens, Jaguar will probably build it." Sports Car World, July 1976.

THE SERIES III XJ (1979-1992): In 1979, the SIII XJ was introduced. This model was a smashing success for Jaguar, producing record sales and giving the company a new lease on life. Pininfarina of Italy subtly redesigned the series II XJ6 body with great success and the resulting design has aged exceedingly well - becoming the model for the current X300. The roof line was extended slightly for more rear headroom, rear tail lights were modernized, the door handles made flush, the bumpers became better integrated into the body and the vertical bars on the front grill all made for a much better effect.

In spite of the beautiful new body, early SIII's suffered the same quality control problems which plagued the SII's. The 1979 Series III was, in fact, the source of the infamous joke about, "It takes four Jaguars to complete one road test." That test was run by Road and Track; it took them four cars to have one machine long enough to complete the test. While they were impressed by the advances made in the car's design, they were less than overwhelmed by such reliability.

In 1980, Jaguar left the huge British Leyland manufacturing conglomerate and became an independent company again. In 1981, Jaguar management began a tremendous effort to correct it's dismal quality control record. XJ6's produced during this period still suffered from numerous build and component defects, but the situation slowly started to get better. For the buyer who is comfortable fixing their own cars, these XJ6's can be tremendous bargains.

"Then there are the XJ series, saviors of the company's bottom line in recent years, a success story in modern internationalization as the managing directors made parts suppliers directly responsible for the warranty costs associated with the car's failures. Simply put, if a Jaguar had to be repaired under warranty and the failure was due to a component purchased from one of the factory's approved vendors, that vendor had to pony up the pounds for the customer's warranty work, not Jaguar Cars Limited. You can believe that this got the attention, not only of the folks at Lucas and Bosch but around the world." Scott Fisher (

Late in the 1982 model year, the car's electronics were extensively revised, and many small but important revisions were made to engine components. Overall build quality improved immensely, as Jaguar began rejecting parts that did not meet exceptionally high standards and had a housecleaning on quality control and assembly staff..

"...the 82.5 cars are VASTLY superior to the ones that went before; my late 82 is as new, very well built. Not a squeak or rattle, and of the 4 xj cars I have owned, including the V12 cars, it is the quietest. It has proved to be perfectly reliable in service. As far as I am concerned the quality of this 82 easily matches that of my 84, 87 and 88 [XJ12] cars." Dr. Gregory Andrachuk (

1983 brought other changes; the dashboard design was improved, with more wood, toned-down switch graphics and an electronic trip computer for the Vanden Plas. Further small engine changes were made this year. The following year, 1984, saw the trip computer made standard across the line, as well as additional small in-progress improvements to the engine.

This same year, Road and Track reviewed an XJ6 and tried to get it to blow up - they failed. They picked another one and did the same thing. It wouldn't blow up, either. They seemed to like it.

"The first example in this test was driven hard for over a month.

Nothing went wrong.

When that one went home, we swapped for another, an XJ6 with the standard interior. That one was used for another 1500 miles, as long and as hard as good manners allow. It was kept idling in parking lots, crept through rush hour traffic, cruised through the desert at unprintable speeds.

Nothing went wrong. The needles stayed at the center of their dials. There were no mysterious noises, no showers of sparks, no puddles of steaming green coolant.

This is wonderful news. Later logbook notes reflect the pleasures of driving a car with character, one that somehow imparts to the driver more flair, more polish than otherwise displayed. The XJ6 has always been a driver's car. Now it's one that can be driven there... and back." Road & Track, July 1984

Improved paint application was brought on-line in June of 1986. Many pre-'86 Series III XJ6's have poor paint jobs, this is unfortunately normal. Sovereign and Vanden Plas are the luxury trim packages.

"I personally prefer the Series 3 cars. Late Series II's have FI, as do Series III's. In this application its a good thing, the cars start and run beautifully, which is something that cannot be honestly said of the carbureted cars." Joseph Augenbraun (

For the average buyer to use as a daily driver, a 1986 or 1987 Series III XJ6 is probably the best choice, though there is some thought that the mechanicals of the 84-85 cars are slightly better. These are the nicest, the most reliable, have the best paint, while being free of the electronic wizardry and headaches of the XJ40. For the non-US market, a post-86 XJ12 is sure to be a good choice, though you might not like the fuel bills the mighty V12 will rack up.

2. Specific major problem areas with Series I thru Series III XJ's.

When buying a used XJ sedan, the first step is to do some basic research into which model is best for you. Certain Jaguar models are performance oriented, while others emphasize comfort and luxury, some were put together poorly and others well. A good start is to look through some of numerous books available outlining the various model designs and differences.

Once you've narrow your choice down to a specific model, you can begin patiently searching for a solid example of that model. At this step, it is extremely important to find a well maintained car. Full documentation that quality work was done on the vehicle is essential to establish this. A poorly maintained Jaguar will present you with a host of expensive hidden problems.

"In the 24 years I have been working on Jags, the ones I have seen go the distance are the ones that were maintained properly, watched like a hawk. They aren't a car you can drive like a Japanese import (add fuel and go), but nothing rides like a Jag..." Loren Lingren (

"I would not buy a late model used car unless it had a complete documented service history showing that all recommended maint. items had been carried out on Jaguar's schedule. I also like to see that the work was done either by a dealer or a Jag specialist shop. Only 1 in 20 or so cars meets this standard, but they do exist and you really want a car that was well maintained. By looking through all the records you can also get a feel for whether or not the car has recurring problems and if typical major items (i.e. steering rack) have already been handled." John T Horner(

The following is a list of serious problems reported by a number of members of the Jag-lovers list. Please do not be alarmed by what appears to be a large list. It is very doubtful that any single car will suffer from all of these, but many of these problems are seen again and again.

Rust: Rust in the XJ first appears in the fender lips under the front turn signals, around the wheels, in the front jacking points, under the rear bumper and mufflers, in the lower seams of the doors and trunk lid.

Rear radius arm mounting points: If the car shows any signs of rust, it is extremely important to get these checked by a professional. These very vulnerable parts is located below the rear seat and is essentially the pieces which anchor the rear suspension to the body. These are very susceptible to rust and can be terminal if left untreated. Repairs to this area involve unpleasant and sometimes complex welding.
Coolant problems: Jaguars have a reputation for overheating. The XJ coolant system runs at high pressure (15 psi) and a leak anywhere in the system can cause serious problems, such as a warped head. A good XJ6 should run at 88 degrees Celsius. If the temperature gauge reads any higher than 95C once the car is warmed up, you will have problems. See the coolant FAQ for more information on this.

Worn Cam Followers: When the cam followers (aka tappet guides) become worn they can pop out, destroying your engine. The usual symptom is loud ticking or clicking coming from the under the cam covers when the engine is idling. The exhaust side is the most prone to wear. Jaguar has a retrofit kit which holds the cam followers in place. As with so many fixes with this car, it is about $30US for the kit itself and $250US for labor. This work was done on many cars. You should ask if a 'Stakedown Kit' has been installed over the cam followers.

"I have been self employed since 1957 with an average of 3 to 5 mechanics in the service department, and for 14 years I was the Jaguar dealer and attended many dealer training sessions. I consider myself to be an expert.
In the early days of Jaguar XK120 to XK150 the fix for this problem (loose tappet guides) was a grub screw, this did solve the problem. The modern fix is the tappet retainer plates, it is a quality professional fix that was recommended by Jaguar Cars. I have seen Jaguars with the tappet sleeve completely broken up. We have used this tappet retaining kit on all loose tappet sleeve for many years without a problem. I would put a tappet retainer kit in any Jaguar I owned up to a 1987 XJ6, whether there was a click or not." Norman Nock

Timing Chains: A worn timing chain or maladjusted cam tensioner will make a clicking sound in the front cam covers. Loose timing chains are easy to fix, worn out chains are not. The timing chains themselves are cheap, but they require a lot of expensive shop time to get to.

Front main crank seal: The XJ6 main seal design is awful. Expect to replace it every 40K miles no matter what. Every British engine I have ever worked on (and most of those I've seen) leak here at least a little. It's a design feature... I think. It's also a pain to swap out - but not fatal.

Paint: Paint on most XJ's thru 1986 was terrible. Improved paint application was brought on-line in June of 1986. The paint on XJ's built before this time is rather poor, suffering from cracking, bad clearcoat and general deterioration.

Gas Smell: There is a jungle of fuel lines in the floor of the trunk servicing the twin gas tanks. There are also some vapor recovery cans back there too. When the hoses get old and cracked or the vapor canisters are saturated, you can get gas smells. A devious way to get the price down on an XJ you are buying is to overfill the gas tank, flooding the recovery system and producing overpowering gasoline odors. The problem is, you have to get rid of the odors later...

"The XJs are often maligned for the typical reasons: (1) poor quality control at the factory, and (2) American owners who do not understand the level of maintenance _required_ by a British car. Once you have found an XJ6-III that was built correctly, there are 2 major weaknesses in the design. One, the main seal design is awful. Expect to replace it every 40K miles no matter what. Two, when the cam followers become worn, they can pop out. Jaguar has a retrofit kit which holds the cam followers in place. It is about $300US. This work was done on my car. Some of the gadgets don't work quite right on my car. No big deal; I will get around to them when I have time." Ron Knipper (

Previous Owners: Many people do not understand the nature of life with a Jaguar. While not onerous, these sedans require a little bit more maintenance than, say, the typical Toyota Corolla. In addition, there are several service procedures unique to the XJ that even well-intentioned owners may miss. More often, though, the owners neglect them out of ignorance, and a simple problem becomes worse. Make sure it has complete maintenance records, and that the facility performing them was trustworthy. If this is not an option, you must have the car checked out by a Jaguar specialist familiar with the type. Sit down with the owner and the owner's manual, if it has one, and go through the "recommended service" items and inquire if these things were done, then verify with the specialist. On the discussion list, the previous owner is often thought to be the biggest problem with these cars.

3. Other common problem areas with Series I thru Series III XJ's.

These are some other common, yet, less serious, problem areas reported by XJ owners on the jag-lovers e-mail list:

Gas mileage: Jaguar sedans are very heavy. While this affords for good accident protection, gas mileage suffers proportionally. Expect to see 15-18mpg from these cars, and less if you have a V12.

Steering rack leaks: Leaks in the XJ steering racks are common. The fix is to either install new seals ($40+labor) or a rebuild rack (~$260+labor)

Steering rack bushes: From what I hear, _all_ Jag XJ cars need these all the time. They are the first thing I fixed on my car. I did it in the driveway with no special tools. Took about 4 hours. There are now polyurethane bushings on the market - current reports indicate much better (and longer lasting) results than with the stock ones referenced above.

Coolant temperature sensor: failure of this component will result in the engine running very rich when cold, pouring black smoke out the back and refusing to accelerate when 'asked' to. Easy fix.

Oil Sender leak: If it leaks from the threads, tighten it some or use some Teflon thread tape on it. If it leaks from the body, replace it. No big deal on an XJ6, but who knows on a 12?

A/C Failure: This is important to check. Believe it or not, this can put you on the side of the road on a hot day. The fuel line runs next to the hot engine block and then goes thru a fuel cooler built into the A/C system. If the A/C is out, eventually you get a vapor lock when your fuel gets too hot. This has happened to me personally and to other XJ6 owners that I've talked to. A/C failures other than hose or compressor issues are often extremely expensive and complex repairs. Think long and hard about a car that has A/C problems - and if you buy it, it should be at a price well below local market average.

A/C Hoses leak: All A/C hoses leak to some extent. The most common explanation (urban legend to follow!) is that the Freon molecules are small enough to seep through the molecular structure of the hoses. If they leak badly or from the joints, they need to be replaced which is $$$ on any car anymore. Some have reported success for hose 'porosity' using system sealers which are available. YMMV

Brake Rotors: If they're evenly worn, and there is plenty of pad, this is something to worry about later. Rotors for the 6 are not very expensive (something like $30 or so each, I think), maybe more for the S. Rear brake renewal on XJ is a expensive job due to the excessive time required to do the job - the rear subframe must come out to replace the rotors.

Transmission: The Borg Warner Transmissions are relatively clunky, susceptible to heat and when they wear out, they are very worn out. Watch out for slow or nonexistent gear changes, strange noises, like whining, or leaks.

Valve cover leaks: Easy to fix on a 6, probably a pain on an 12. Parts are cheap for this though, and if you use a proper sealer (blue RTV seems to be one of the sealants of choice, the copper stuff is good too), it should remain leak free for quite a while. The gaskets all by themselves won't seal well for long.

Cruise control inoperative: This was an easy fix on my car (after a painful diagnosis). There is a disengagement switch on the brake pedal mount (next to the brake light switch). One of the wires to this switch _broke_ at the crimped on connector. I fixed it, and it repeated after about a month. A second, more careful fix seems to have remedied the problem. There is also a bellows that seems to like to come unsealed. Resealing is the fix.

Dead XJ12 ignition module: Heat tends to kill the ignition amplifier modules on V12's and, to a lesser degree, on the 6's. A common modification is to move the module to a cooler locations in the engine compartment. Replacement GM HEI module (Borg-Warner CBE-4, around $35, plus your time to replace the module) have been used successfully in place of the expensive Jaguar units.

Trip Computer on the fritz: If you have an electronics background, these look simple inside. If you have techno-phobia, they're scary. Expensive to replace, but not really a necessary item in any case. I have found the mileage reports to be so depressing that I just use mine as a clock.

Speedometer/Odometer failure: The transducers in the speedometers are prone to failure. The clever DIYer can fix these.

"Note that on an XJ it is frighteningly easy to remove the speedometer/odometer. (Just press and turn). Thus be careful of those low mileage cars which were only driven to church on Sunday. I often suspect mine was tampered with in that the speedometer face has lots of fine scratches which are on no other gauges." Mike_Israel (

Electrical Switches: There are many electrical switches in the XJ6. Make sure all the window switches ($30US) and door-locks work. Make sure the gas-tank switch (the fuel gauge will show the changeover) and the rear heater grid switch works properly. Inoperable window switches are often fixable with a good cleaning.

Other expensive items: Rear axle seals (A common problem and a bear to replace, about $500.00), stress cracks in front shock strut housings, dead power antenna, leaking hoses (watch especially for fuel lines feeding the injectors), leaking transmission, leaking gas tank, bad front suspension (especially ball joints), overheating,

"Overall, if you like to work on cars, and have some aptitude, these cars are not bad to work on. In fact you'll find features that are _way_cool_ and wonder why everyone doesn't do it that way. (eg, fan belt tighteners). A while back, on the brit-cars list, Scott Fisher #1 spoke of 'a comfortable level of wrong'. There will always be something less than perfect about any car, especially one as complex as the Jaguar XJ series. A Toyota corolla is child's play by comparison. Me, I like the way the car is put together, the way it looks, the way it drives, and the way it feels. I can put up with a bit of "wrong"." John R Dombey (

"There are a couple of modifications that every XJ6 should get. The steering rack is held in with wimpy foam rubber bushings; sliding in a couple of washers to limit movement transforms steering response. FI cars come from the factory set too lean and with too slow response on the air flow sensor. Breaking off the potting compound to get in and make these adjustments is rewarded with 0-60 times decreased by a second and a half, and no problem passing emissions either. XJ6's are famous for cooking their transmissions. This is due to inadequate cooling of AT fluid in the radiator; an aftermarket transmission cooler should be installed. Every 6 cylinder Jag engine needs tappet guide hold-down plates installed at 40k miles. Any car without these will make horrible knocking sounds even at idle. Installation is an easy two-hour process. All XJ6 catalytic convertors clog at 70-90k miles. Replace or ream it out, or you will lose the head gasket at 100k miles." Joseph Augenbraun (

4. Prices of XJ's:

As with any used car, there is no foolproof method for determining what the correct price of a used XJ should be. One metric is to see what similar cars are selling for in your local paper. An upper bound for the price can be usually be determined by looking at the prices being asked in the US publication "Hemmings Motor News". Vehicles advertised here tend to be in excellent shape and priced accordingly.

In the western United States, the prices for running Series III XJ6's appear to have bottomed out at around US$2000-$3000. XJ6's at this price level usually are high mileage cars which have been driving hard and may require a lot of work make right. Anything below this price level is likely to be a basket-case. For US$6000-$8000 you can find XJ6's in good condition and any priced more than US$10000 should be have low mileage and be in excellent condition. Here, series I and II XJ6's typically go for much less than the series III cars. XJ coupes and newer XJ12's are more valuable than equivalent XJ6 models, while older XJ12's are less valuable.

"What to beware of? Beware of the PO (Previous Owner). Don't take anything for granted - look at the brakes and rotors with your own eyeballs, drive the car while ignoring how nice it looks and feels and possibly smells - pay attention to the lumpy idle or lack of power at high speeds. Ask who's maintained it, call the service dept., give them the VIN, and get the car's pedigree. They should read to you the service history. The recent threads about tires - important. There are tires that fit, and there are tires that fit *and* are correct. Cheap-o tires are indicative of a cheap-o PO. I always overkill on tires." David J Shield (

"From my own experiences I will pass on some oft repeated words of advice for future Jag owners: 1) Buy the very best Jag you can afford. You are better off paying a premium than sinking $3,000 into a lower cost vehicle and then never really trusting it. Look for those dealer service records. Had I spent another $2,000 up front and also had it checked out by the dealer I would likely not be trading it in after three years. 2) Get the vehicle checked out by a JAGUAR mechanic BEFORE purchase. I paid $70.00 to get mine checked out by a "we fix anything" shop and they failed to notice MANY problems unique to the XJ6 which were there when I bought it. Again, penny wise and pound foolish." Mike_Israel (

5. Miscellaneous XJ topics:

A. Engine:

The 4.2L XK engine: The Jaguar "XK" engine design is one of the most successful designs in British motorsport. Originally designed as a racing engine in the late forties, the XJ engine is a double overhead cam straight 6 which was available first in the XK120. The engine came in a number of different sizes ( 2.8, 3.4, 3.8 and 4.2 litre) with the 4.2 litre displacement being the most common XJ6 engine. Compression ratios ranged from about 7 to 9 depending upon the year and market. It was available with twin Stromberg 175's, twin SU's of similar size, three 2 inch SU's and, finally, with the Bosch L-Jetronic fuel injection system.

"The race-bred heritage of the XK engine seems to be one of the main character-bearing features which sets a Jaguar apart from almost any other car. When matched with Jaguar's wonderful wood/leather interiors and the curvy "fenders like hips under silk" body designs, Jaguars have an incredible draw on me, to the point of becoming an irresistible vice. " Lawrence Buja (

The 5.3L V12 engine: XJ12's, equipped with the Jaguar 5.3L V12 engine, were built in SII, SIII and XJ40 platforms. The XJ12 is not for the faint of heart. While the Jaguar V12 engine is considered grossly overcomplicated and maintenance intensive, they are truly awesome if you have a big enough wallet to support them. Improved, high efficiency (HE) May combustion chambers for the V12 engine were introduced in mid-1981.

"As for reputation of this car and engine (XJ12), let me first say that you had better be an enthusiast/collector. This is a car that needs to be looked after constantly. The frame of mind one should have is to treat this car as a collectible, to be driven once in a while or on weekends. Road and Track did a survey at that time, and found the XJ12 to have 21 problem areas. At the same time, this car also has immense appeal; it has a beautiful body, beautiful interior, and even a beautiful engine." Roger Peng (

"In the last 5 years, I have repaired/replaced heads on 8-9 overheated V-12s. Usually there are multiple problems all related to heat. Many of these had dropped exhaust valve seats, due to heat, causing more damage than just a bent head; broken pistons, two broke cylinders liners, several had heads bent beyond the point of salvage. New heads from Jag are approx. $1025ea. It PAYS to watch your engine temperature on any Jag, since parts to repair are not cheap. Like Michael Neal, I had one customer with an XJS & 208,000 on these engine (he bought it new) and it hadn't been apart. Of course he was on his third transmission." Loren Lingren (

The 350ci Chevy V8 engine: While a case can be made for transplanting a non-Jaguar engine into a Jaguar, the end result is something which is not considered a Jaguar. Accordingly, this subject will not be discussed here.

B. Fuel Injection:

"The injection in the XJ6 is Bosch. The design is Bosch, the patents Bosch. The parts are either made by Bosch, or by Lucas under license. Most, if not all, parts are Bosch made on the XJ6. The system is known as the Bosch L-Jetronic system. If a local mechanic can not work on it, he had best turn in his vise-grips. The system is *common*, either in Bosch form, or based on the Bosch patents. Most car makers, European, Asian, and American alike, have used L-Jet or one of it's variants. Everything from BMW's to Yugo's. 280Zs to Beetles. Fiat, Truimph, and Ford. The is no mysterious black magic in servicing and repairing that injection system." Randy K. Wilson (

C. Transmissions:

An XJ6 fitted with a manual transmission is a rare find, most XJ6's were built with 3 speed Borg-Warner automatic transmissions. Early XJ6's were fitted with the BW12 and BW65 automatic transmission. In 1982, a transition was made to the upgraded BW66 model. These 3 speed automatic transmissions are perhaps the least sophisticated feature of the XJ6. Though smooth, they are relatively slow and a bit agricultural. However, these transmissions have turned out to be relatively robust. The downside of this is that when they wear out, almost every part is worn out and it is often not economical to rebuild them. The later XJ12's came with a GM Turbo-Hydramatic 400 three speed automatic that has proven quite reliable in daily service. Earlier models had the Borg Warner BW12, which has received mixed reviews. Some owners have replaced their BW's with GM automatics or Toyota manuals. Other replacements are available, those two being the most "common."

"The XJ6 used a Borg Warner BW66. This box is unique to the Jag, but has cousins in everything from AMCs to Volvos. " Randy Taylor (

"At 62,000 the BW (Borg-Warner Transmission) swallowed itself and spit out lots of little bits of metal then died. I had the choice of big $ and a new BW or big $ and a TH350 that could be replaced next time for $350. I chose the latter. My intown mileage went up from 14.7 to 16.0 and the highway mileage at 75MPH went from 22MPG to 24.5MPG. I have put 40,000 miles on it since the installation, and there IS NO VIBRATION, and the U joints are still fine. I understand all the concern, but I really think 40,000 miles speaks for itself. I only got 60,000 miles out of the BW tranny in the first place!!!! Again, I repeat, 40,000 miles, read my lips, 40,000 miles and not a bit of vibration, noise, or maintenance problems. It speaks for itself. This is a 1982 XJ6 fuel injected 4.2 litre in a very hot climate (Texas)." James A. Isbell (

"Regular fluid changes will keep that smooth BW66 operating perfectly [for] well beyond 100,000 miles, as I know from experience." Dr. Gregory Andrachuk (

D. Suspension:

"The fine handling / ride characteristics of XJ6's are a result of a huge number of difficult-to-replace rubber bushings. These degrade over time and miles. Even though they have identical suspension, you will think that a 1976 is a fair to middling car and a 1986 strikes the finest balance between handling and ride you've ever felt on a softly sprung car. The difference is the dry-rotted bushings. (The bushings aren't expensive, just time- consuming to replace)." Joseph Augenbraun (

E. Differences between European Spec XJ6's and US XJ6's:

European specification XJ-6's were commonly brought into the US as "grey-market" imports in the 1980's. The European models had some minor differences from US models, which may be important if you live in an area of strict emission rules. The European XJ6 may or may not have: 1) A catalytic converter, oxygen sensor, air pump or other smog gear fitted to the US cars. 2) The standard 4.2L found in US cars. Some European motors were smaller displacement 2.4 or 3.4L engines, while others are higher performance high-compression 4.2L engines which require high octane fuel 3) Large 7 inch outboard headlights with wipers and smaller 5 inch inboard headlamps. US versions have the same sized headlights in both inboard and outboard positions with no wipers. A chrome flashing is used to compensate for the smaller outboard headlight.

F. Books about the XJ6 Saloons:
The XJ-Series Jaguars (Jaguar Collector Series)
Paul Skilleter, 144 pg, 180 ill, $27.95

Jaguar XJ: The complete Companion (*NEW*)
Nigel Thorley, 168pg, 120bw & 20 color ill, $29.95

Jaguar XJ6 Series II, 1973-1979 (Reprinted Reviews)
Brooklands Series, 100 pg, 215 ill, $15.95

Jaguar XJ6 Series III, 1979-1986 (Reprinted Reviews) (*NEW*)
Brooklands Series, 100 pg, 180 ill, $15.95

Jaguar XJ12, XJ5.3, V12 (1972-1990) (Reprinted Reviews (*NEW*)
Brooklands Gold Series, 180 pg, 300 ill, $21.95

Jaguar Project XJ40. The inside view of the new XJ6.
Philip Porter, Haynes Publishing, 1987, 176 pp., $34.95

Jaguar XJ40: Evolution of the Species
Andrew Wythe, 192 pg, 177ill, $24.95

Jaguar XJ40
Piero Casucci, 100 pg, 80ill, $49.95

T.E. Warth's Jaguar Book List (large listing of collector Jag books)
David Moe, Spiralbound, 26pgs, 112 titles, $14.95

Available through Classic Motorbooks
US: 800-826-6600, FAX: 715-294-4448, Overseas: 715-294-3345

Jaguar World (UK)
British Car (US)
Hemmings Motor News (US)

6. Jaguar XJ6 quick reference.

  Series I   (1968-73)

     XJ6  : is the dual overhead cam inline 6 cyl. 4-door car.
            - 0-60mph in 8.8 secs.
            - Large, almost unsightly grill.
            - Gothic taillights shaped like a cathedral window ().
            - Door handles stick out from the body.
            - Chromed steel wheels
            - Chromed bumpers

  Series II  (1973-79)

     XJ6  : Same engine/body shell as Series I,
            - Grill is much smaller than series I, front bumpers are raised.
            - Bars on grill are horizontal.
            - Gothic tail lights retained.
            - Door handles stick out from the body.
            - Chromed steel wheels
            - Chromed bumpers except US export
            - BIG ugly black 5mph overriding bumpers for US export

     XJ6L : The "long wheelbase" version of the XJ6 that is four inches
              longer - all in the back seat floor/knee room area.

     XJ12 : The 5.3L V-12 engine version.

     XJC  : a quite rare 2-door coupe' version of the XJ6 and XJ12.
            (Some non-factory customized XJC convertibles exist)

  Series III  XJ6: (1979-1986)       XJ12: (1981-1992)

     XJ6  : Pininfarina subtly redesigns body.
            - 3.4L and 4.2L straight 6 engines.
                202bhp @ 5000rpm;   227ft/lb @ 1000rpm
                0-60 in 10.0sec,  127mph max, 16.8mpg
            - 112.8in wheelbase, 3978 lbs unladen.
            - Bars on grill are vertical,
            - Door handles are flush with the body,
            - Tail lights are bigger, semi-circular or "crescent" shaped.
            - Roof is raised slightly with thicker
              rear roof support panels
            - Alloy wheels of various designs
            - Big black bumpers
            - Sovereign: add alloy wheels, trip computer, AC,
               electric mirrors, carpeted boot, rear head rests.

     XJ12 : The 5.3L V-12 engine version.  Manufacture ceased in 1992.
            - 0-60mph in 8.1 sec, 150mph max, 16.4mpg
            - Final XJ variant to be produced - last 100 cars carry plaques.
            - Not imported to the US for CAFE reasons.

  Other model variants:

     Sovereign: Luxury version of the XJ6 loaded with options.

     Daimler: The non-export, upscale Jaguar badge.  Daimler is to Jaguar
               as Mercury is to Ford.  Characteristic features are a
               fluted grill and tail plinth, slightly different interior
               treatment.  Usually fully loaded with power options and
               fluff like rear headrests and picnic tables.

     Daimler Double Six: Daimler version of the XJ12

     Vanden Plas: Export version of the Daimler

Revised 10/12/2000 by Henry Fok,

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