2003 Cavalier loses power Code P0171

[jlklein]

Hi all,
Been awhile since I've posted. This is for my son's car, a 2003 manual Cavalier sedan. Bought it used from a high school kid with 40Kmi last year, got about 62K now.

Friday my son called and said it died on the highway on the way to his girlfriend's, lost power and check engine light came on, and he had to pull over. After sitting for a short time he got it going again (I don't think it ever completely died). We drove to his girlfriend's house and followed him home, about a 20-30 min drive on mostly highway, it died again right before our exit. He got it going again and we limped the last 5 miles to the mechanic's, able to do 20-30mph fine, good thing the speed limit was that <G>.

Mechanic replaced the fuel filter (reported it as very heavy and barely able to push air through it). Ran fine a couple days, but mostly stop and go driving. Son took it to Six Flags, about 30 minutes away, mostly highway, died again on the way back and check engine was back on. Got it home after sitting a bit.

Took it to Advance Auto, read code out as P0171, System Too Lean, (Bank 1). I'm driving it now and seems okay still, but I'm not doing prolonged highway trips. Engine revs seem fine, about 2-3K at highway speeds, temp hangs around 125 deg. No other warning lights.

Any ideas? I see a lot of similar symptoms with others' Cavaliers, hoping that this code will help me (and others) out.

Thanks,
Jeff K.

[bbaaspencer]

I know a plugged up gas filter will cause a P0171. The plugged gas filter will also ruin the fuel pump. Common problem in 2003-2005 Cavaliers is not changing the gas filter and it will burn up the electric fuel pump. The P0171 can be caused by a vacuum leak.

[Tech II]

Sounds like a fuel pump on the way out......only way to know for sure is driving it with a fuel pressure gage attached......

Otherwise, keep a can of Carb cleaner in the car....if it dies and won't start, spray carb cleaner into the intake, and see if it starts, if it starts and dies once the carb cleaner is burnt up, either pressure or injector problem....money is on the pump....