usnfenix

iTrader: (11)

ive been having a prob for awhile now i just got done doing lt headers about 2 weeks ago and ever since then theres been a slight vibration during driving, its slowly gotten more noticable as ive driven more and more. its began to have a rough idle at stoplights and such. yesterday it was fairly noticleble and i thought maybe a plug was loose. then today it took a massive **** all of a sudden. extremly rough idle and the whole car is shaking roughly. the ses light which has been on for awhile ( running lean codes p0171 p0174 p0420 ) started blinking and the car was shaking and felt like misfiring was happening, i couldnt even get the car above 20 mph it was so bad. sitting at stoplights trying to limp the car home it came close to dying many times. ive checked the plugs there on there solid and there brand new ngk v power tr55 and ive got brand new msd wires as well, none of them were loose. when we did my headers however during splicing of one of the front o2 sensors we got them mixed up and had to guess which ones went where. that was 2 weeks ago. ive read that bad o2 sensors could cause this and is sort of common after exhaust swaps involving the sensors. is this my issue? need help car is my only one and need to drive to work

on a side note im aware that those wires could be mismatched and this could be my problem but do the symptoms match?

Darkman

iTrader: (2)

The p0420 is not supposed to set if either of the lean codes have already set. I would start by clearing all the codes (disconnect the battery for 30 minutes will do it if you don't have a scanner) and see which code sets first.

usnfenix

iTrader: (11)

that code if im reading correct is for the cats which are no longer in the car as of the header swap. my bad for putting that in post that code popped after header install but i never cleared it. the lean codes are the new ones and since now i cant even drive the car and the ses is blinking its added a misfire code

Darkman

iTrader: (2)

Okay. I assume that you did not tune the engine following the header install. A post-header tune should include turning off the post-cat sensors in the ECM such that the related code never sets.

In any event, the other two codes are as you said are lean codes. Assuming the lean condition is not a tuning issue (add headers usually causes a rich condition) you are getting either: (a) too little fuel; or (b) too much or mismeasured air. On the fuel side that can be caused by contaminated fuel, blocked fuel filter, or too little fuel pressure (fuel pump), clogged injectors. Since both banks are setting codes the clogged injectors are the least likely.

On the air side, you may have a vaccum leak (tubes, manifold, throttlebody). It could also be contaminated MAF sensor wires, which can be cleaned with CRC MAF cleaner (be careful - some chemicals will kill the MAF).

Finally, it could be problem with the front OS2 sensors including the wiring/connectors.

usnfenix

iTrader: (11)

i think if it is o2 sensors the rain was a factor here. yesterday, the day it took a crap, there was heavy rain and several large deep puddles on the road that i went through minutes before it started. i looked under the car and the passenger side front o2 wire bundle is hanging very low and def was dragged through some puddles, i also noticed there was no protective sleeving covering the wires and there connections, just the wires tied together. im thinking this is the problem and the rain accelerated it. ive read a couple other forums with similar symptoms and it turned out to be o2. and i read one also where a guy was driving in the rain and an o2 craped out on him and casued misfires on that side of his engine, similar to whats happening to me, the passegener side sensor is the one hanging and its passenger side that is misfireing

Darkman

iTrader: (2)

Water intrusion is definitely a potential issue for the O2 sensor circuit - it is often listed as one of things to check for in the GM troubleshooting charts.