PDA

View Full Version : P0171 causing CEL

JayCizzo
April 10th, 2009, 1:27pm
Well I've also gotten the P0171 intermittently, but now I'm getting it constantly and it's causing a CEL. I go, clear the DTC's, the CEL turns off, and then in about 2 seconds the CEL comes back on and when I check the codes I've got another fresh P0171 in there. :(

Any suggestions?
bc3tech
April 10th, 2009, 3:24pm
going lean, tune might not like the warmer weather - check it, and/or reset your fuel trims w/ a battery unplug for 30min
JayCizzo
April 10th, 2009, 3:41pm
going lean, tune might not like the warmer weather - check it, and/or reset your fuel trims w/ a battery unplug for 30min

Thanks, I can give that a try but the tune was done during the hottest part of summer here in Florida so that doesn't seem likely to me.
MGM1979
April 12th, 2009, 12:45pm
check the intake track/tubing again?

when was the last time you cleaned the air filter - it might be dirty/clogged...and, your favorite - that TB plate.


other than that - could be bad tank of gas...or, worst-case, failing injector...obviously, take it easy on her until you nail it down.
JayCizzo
April 13th, 2009, 10:13am
check the intake track/tubing again?

when was the last time you cleaned the air filter - it might be dirty/clogged...and, your favorite - that TB plate.


other than that - could be bad tank of gas...or, worst-case, failing injector...obviously, take it easy on her until you nail it down.

So, on my drive home of the same day, I cleared the CEL as soon as I started the car and drove home (25 miles) and the CEL didn't come back. Weird. I will check all the things you recommended as soon as I can. Car pooled today in Steph's car so no worries. Thanks.
MGM1979
April 13th, 2009, 12:05pm
ahh...carpooling in a RELIABLE car - yeah, that's always an option too!

;)
Doc
April 13th, 2009, 7:10pm
You need to increase your MAF frequency. I don't have the software with me and the internet is REAL slow. Anyway, set it for 12.5k I believe....I'd search on .net for 0171 but it'd take me an eternity to get anything.
JayCizzo
April 14th, 2009, 11:36am
Matt, Any idea what my MAF frequency is set to? When's your next trip to Florida? LOL
MGM1979
April 14th, 2009, 1:38pm
Matt, Any idea what my MAF frequency is set to? When's your next trip to Florida? LOL

I'm guessing 11k - I think the factory setting was 10k...either way, you've been running that tune for a while, so the only reason the MAF setting would need to be adjusted would be if the air conditions changed drastically while you were having the issue...another possibility, if you haven't seen it come back in a few days.

I've still got a hedge bet on a tank of bad gas too...