P0172

Tiny
WJ2893
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  • PONTIAC
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?
Thursday, March 15th, 2007 AT 6:17 PM

3 Replies

Tiny
2CARPRO JACK
  • MECHANIC
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Tune up with OEM parts?
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Friday, March 16th, 2007 AT 7:56 AM
Tiny
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. :)
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Friday, March 16th, 2007 AT 10:51 AM
Tiny
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. :)
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Sunday, March 18th, 2007 AT 5:20 PM

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