p0172

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WJ2893
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1996 Pont.Grandprix,3.1,100000miles.p0172 system to rich bank 1. I am unable to get rid of this code.I have done a complete tune up,plus these new parts and sensors converter,o2sensors,mass air flow,map,throttlepos.idle air control,egr,gas cap.Also fuel press. is good. The car runs great but will not pass inspection if I just keep erasing the code.What else could this be?
Mar 15, 2007 at 6:17 PM
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2CARPRO JACK
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Tune up with OEM parts?
Mar 16, 2007 at 7:56 AM
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PEPPERMRJ
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Does it smell like it is running rich?
Are you using a K&N air filter? An oiled filter can play hell with a MAF even when it is new.
Did you replace both the upstream O2 and the one after the cat? Any exhaust leaks?
Check for vacuum leaks @ the hoses and Map.
What fuel pressure did you get with the engine off? Does the pressure bleed down?
Does the pressure fluctuate with the engine running?

I'd bet on a fluctuating pressure regulator or a leaking injector. Try some injector cleaner or have them professionally cleaned. I like chevron with techron.

Good luck and let us know. :)
Mar 16, 2007 at 10:51 AM
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PEPPERMRJ
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From: wj2893
To: peppermrj
Posted: Sun Mar 18, 2007 2:08 pm
Subject: p0172
"Thanks for the input regarding my problem on this code.I found that there was a pinched return fuel line and the problem is now fixed. thank you again,Bill "

Thanxs for the update. :)
Mar 18, 2007 at 5:20 PM