Ok so I bought a 05 sunfire (110,xxx miles) with the GMPP M62 kit on it. I removed the kit bought some used injectors had them cleaned put on a new FPR, new MAP sensor, new plugs, stock air box and a used PCM flashed with my VIN. Stock exhaust.

It was throwing several codes a couple of weeks ago but the P0171 is still hanging on. Once it is warmed up it pulses at idle and when accelerating from a stop will die unless revved past 3k. When cruising in 2nd or 3rd at slow speeds when the throttle is presses it will hesitate/bog down then surge hard and accelerate almost normal. Could these symptoms be caused by a clogged fuel filter or a bad O2 sensor?

It seems down on power compared to my other sunfire of the same year. When I was removing the kit I did something very stupid and left those blue paper towels in the intake and sucked em in. I did pull the plugs and intake and pulled it all out and cleaned the injector nozzles. Is there a chance I damaged something?

Any help or ideas would be awesome!


-I drive my car to work-

Also here is a screen shot when I was cruising at about 70 mph. I don't have HP tuners and I use a app to read and clear codes.


-I drive my car to work-

if the fuel trim is lean at idle and ok at high rpm you may have a vacuum leak. injector seals at the manifold are becoming common for eco's. spray some brake cleaner onto the injector cavity while idling to check.

you sure that flashed ECU is good? a tune can be the root of all your symptoms before you even start troubleshooting. Swap ECU's from your other 'stock' car and see if it still persists. You may just have to do the 'relearn' but its simple.


04 Cav. 2dr. 5spd. My DD. 'Nuff said.