Help Car Wont Run!!!!
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From: Citrus Heights, CA
Help Car Wont Run!!!! I was on the way to pick up a new hood for my car, when all of a sudden is started miss firing and stuttering. I pulled off the road and when I would give the car gas, it would die. I didn't have a problem starting it, but it would stutter and stumble and die when I pressed on the gas. For a little history, I did heads/cam a while back and was tuned by hp. Since the cam swap/tune my car smells like gas and drips black condensation-like stuff out of the tail pipes. My tuner however seemed to think my car was running great. Anyway, my car threw an SES code so I bought a code reader and pulled a 0300(random multiple cylinder missfire). I checked my wiring and patched a bare injector wire and reset the code. It ran fine for 2 days without a problem or SES, until tonight. Tonights codes were 151, 108 and 131. The only similar codes in the book are 0151, 0108 and 0131, so I'm assuming that is what they are. 0151=o2 sensor low voltage(bnk 2 snsr 1), 0131=o2 sensor low voltage(bnk1 snsr 1), and 0108=manifold absolute pressure/barometric pressure circuit high input. Does anyone have any ideas? This is my dd unfortunately. When I got the miss-fire code I checked the coil packs and plugs. I checked the EGR on my SLP intake and it was sort of loose, so I tightened it down. Are my 02 sensors shot? MAP sensor? Any help is appreciated.
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From: Fat Chance Hotel
Just from your description it sounds like O2 sensors. I'd start there.
You mentioned patching an injector wire... how is the harness overall?
If you're EGR tube was creating a vacuum leak that would most likely be the cause of the MAP code.
You mentioned patching an injector wire... how is the harness overall?
If you're EGR tube was creating a vacuum leak that would most likely be the cause of the MAP code.
Honestly, it sounds like the tuner didn't tune the VE table. If one of your front O2's goes bad, it will force the car into open-loop. I'm pretty sure that would force the car to calculate fueling based off of the VE table and Open Loop Fuel Air multiplier table.
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We'll, I spoke with my tuner and he said the air/fuel ratio was fine. He thought that the high MAP voltage and lean o2 codes would suggest a vacuum leak. Guess I'll start at the egr tube where it joins with the SLP intake, and then check the map sensor wiring and AIR tubes.
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My tuner stopped by today with his GM tek 2 diagnostics. I was throwing the 108(high MAP sensor voltage), and the computer was dumping tons of fuel in. The MAP sensor voltage would not drop after starting the car like it should. Puffs of white smoke were comming out of the exhaust tips. I replaced the MAP sensor because I had an extra one laying around, and no change. The car won't even stay running now. It isn't looking like a vacuum leak anymore because it would have to be so huge to be causing all this, it would be obvious as to where it was. My tuner suggested I do a compression test next. Does anyone have any clues, suggestions? It isn't looking good so far. 
