Thread: code but no light

I have been getting a check engine light p0171 i got a pcm from intense thinking it would go away and it stayed off for a little bit but came back on. Well the last couple days the CEL hasnt come on but my aeroforce shows the code keeps coming back any ideas why it would do that?

Whelp here goes this one...

What year is your car?

Intense could have loaded the incorrect year MAF tables into it...since you have a Aeroforce...switch it to the LTFT's (Long Term Fuel Trims)...when idling or coasting off the throttle if your fuel trims peg at +16.4 then you have either...

A) An actual vacuum leak...which is what the code P0171 is for...
or..
B) You have to either have a local retune your car or ship it back to intense and have them flash the correct MAF tables in your PCM (Example: '97-'98 cars have the same MAF tables...but then '99-'03 are different)

Did you screw up your EGR delete on the 2004 Impala? Is the rubber T off the LIM dry rotted?

2004 impala ss... Ill check the fuel trims in a bit, they shouldnt have screwed it up i called them and practically beat exactly what i wanted into the guys head. The rubber t is fine and the block off plates are fine. Sorry forgot to mention it started before the egr delete and pcm upgrade. I got the pcm because i thought since i have the headers and etc. i was running lean and needed to get more fuel. Basically I have it narrowed down to a bad/dirty MAF sensor or bad O2 sensor.

The O2 is the sensor reporting the issue, not the cause.

yes i know that now i cleaned my maf sensor and filter and code hasn't come back yet so i believe i discovered the problem.