2002 Chevy Cavalier P0172 system to rich

GHILL8950

MEMBER
2002 CHEVROLET CAVALIER
4 CYL
2WD
AUTOMATIC
136,000 MILES

I just replaced the fuel pump and fuel filter and the car is now running great but I have the check engine light on again, ran codes the only code showing is P0172 system to rich bank 1

here is the freeze frame data

Load 63.1%
Coolant 207
ST FTRM1 -15.6%
LT FTRM1 11.7%
MAP 18.9 inHg
rpm 1526
speed 44mph

any help would be appreciated so I can get this fixed?

3 Replies

RASMATAZ

MECHANIC
75,992 POSTS

P0172 running rich probable causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

+1

Saturday, January 2nd, 2010 AT 3:31 PM

GHILL8950

MEMBER
3 POSTS

I have replaced the air filter and the scanner is showing that it is running in closed loop when the freeze frame data is recorded, I also pulled the vacuum line from the fuel regulator and it is dry so the diaphram is good.

Was this

answer

helpful?

Yes

No

+1

Sunday, January 3rd, 2010 AT 2:52 PM

GHILL8950

MEMBER
3 POSTS

Problem FIXED!

I read in a troubleshooting tree that you can reset the fuel trims, I just diconnected the battery for a few mins and the problem is cured the light has not come back on for several weeks now. The code scanner just erased the codes but did not reset anything. With the old fuel pump not pumping enough fuel the fuel trims had adusted to compesate for a weak pump, When I put in the new pump the injectors were trying to undercompensate which was sending the the code PO172 system to rich.

Was this

answer

helpful?

Yes

No

+4

Friday, January 15th, 2010 AT 2:41 PM