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12.26 - Fuel Fail 26 oxy sensor feedback lean ( Brett Gadzinsky,  )

Fuel fail 26 is . As the engine gets partly warmed up, it stumbles and sets the code. The code will clear when the trouble does, on the next restart.

Possible faults for a FF26 are :

- Low fuel pressure (plugged filter, weak pressure regulator on fuel rail, plugged system)
- Intake manifold air leak (vacuum hoses, intake manifold gasket, evap system hose rot, egr pipe rusted out, problem with air injection system (leaking valve).
- Ignition misfire, (bad plug, wires, cap, rotor)
- Purge valve stuck open (vacuum leak in evap system)
- Oxy sensor fault (not common)
- Bad maf sensor or connections.

Best to start with the ignition system : If the wires, cap, rotor are old, replace them, along with spark plugs.

The catalytic converters may eventually melt plugging the exhaust if the car is ran with the FF alarm on, so don't ignore it just because the engine runs ok.


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