Question about 1999 Volkswagen Passat

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Pulled code 1127

Think it needs co2 sensor changed after running a while hesitates

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P1127 long term fuel trim bank 1 system too rich.

I think you could be right with the O2 sensor. The vehicle should only hestitate at light throttle, but should be okay under acceleration. It may even idle slightly erratically.

I would however, if you have a pulsewidth meter, check the injector pulses, because if the pulsewidths are too short then the O2 sensor is functioning correctly and is actually shortening the pulsewidths in an attempt to counteract an overfuelling scenario, which could be the result of dripping injectors or the like.

As I said earlier, though, I would tend to go along with your O2 sensor fault.



Posted on Jun 09, 2008


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