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Pcm Code EO80, Fuel System Rich: Action:

Code set. PCM turns on the SERVICE ENGINE SOON light.

The purpose of this diagnostic test is to detect a rich condition caused by fuel injection system or by evaporative fuel canister that is purging continuously and causing a rich condition. Code can be set only during sustained steady driving, such as sustained cruise control operation.

When all the above test conditions have been met and block learn is 104 or less, the system turns off canister purge to attempt to lean out the system. If block learn is still 104 or less (rich), the code is set.

Fig 1: PCM Code EO80, Schematic, Fuel System Rich
G91D09356