throws a rear O2 code during WOT? rich?
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throws a rear O2 code during WOT? rich? poured in some amsoil PI stuff (i think its just a cleaner) before filling up. During the cruise home gave it a nice WOT run and got a ton of vibration and it threw a P0157 code. (right rear O2 low volt). The car felt sluggish accelerating and it has been for awhile now. I was chalking most of it up to the bad tranny but Im thinkin it might running rich possibly?
Im considering replacing the plugs/wires now that the car has passed 65k miles. Its been sluggish, especially under 2500rpm. A little bit of hesitation but no misfiring. Stock manifolds/cats/ypipe with open exhaust/no muffler. Thinking that cutting the muffler off played a role a few months ago. Gas mileage seems to a little on the low side.
I guess my question is, did the O2 fault up under that one circumstance or has it been a problem for a while now? Meaning should I replace? No codes thrown in last year pertaining to O2.
thanks
Im considering replacing the plugs/wires now that the car has passed 65k miles. Its been sluggish, especially under 2500rpm. A little bit of hesitation but no misfiring. Stock manifolds/cats/ypipe with open exhaust/no muffler. Thinking that cutting the muffler off played a role a few months ago. Gas mileage seems to a little on the low side.
I guess my question is, did the O2 fault up under that one circumstance or has it been a problem for a while now? Meaning should I replace? No codes thrown in last year pertaining to O2.
thanks
Last edited by JAvenger007; Dec 24, 2006 at 11:26 PM.
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up top once more. I believe the bosch 13111 are good replacements? The bank 2 sensor 2 is which sensor? Passenger side before the cat?
edit: scratch that. Im guessing replacing my rear O2 wont do much as far as how the car is running. Any other suggestions?
edit: scratch that. Im guessing replacing my rear O2 wont do much as far as how the car is running. Any other suggestions?
Last edited by JAvenger007; Jan 2, 2007 at 11:11 AM.
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low voltage means lean you can try o2's but i did and found it a waste of money cuz i needed a new MAF sensor i'de try and clear it and see if it comes back. How often do you do WOT runs? mine only did it under WOT as well and it took me forever to find what was wrong, but the help of a TECH 2 (gm scan tool) and the computer we found what was wrong and i bought a slp MAF and have had no problems since. i was setting two codes tho both rears were doing it. just try to clear it and it might go away. if not replace it. and the sluggishness right now is probably because the light it on mine ran like crap with the light on as well. I lost a ran to an almost stock Golf gti when my light was on 
but beat an Evo MR when it was all fixed 
but beat an Evo MR when it was all fixed Last edited by LILWS6; Jan 2, 2007 at 06:35 PM. Reason: added text
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But the rear two only detect the cats correct? So because its the right rear it couldnt have been affecting my fuel mixture right? I'm changing my plugs/wires right now and ill see if that helps.
It was only that one incident so far. And the light went off after three starts. No light since and i did 5 or 6 WOT runs today.
It was only that one incident so far. And the light went off after three starts. No light since and i did 5 or 6 WOT runs today.
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From: Waukesha,WI
that code its self is a fuel mixture code the rear o2 sensors read how much fuel-oxygen is being mixed. the richer the fuel mixture the the more the voltage goes up. the rear o2s are heated o2s as well i believe. The mixture being lean would set the code you have but i would assume its either that one sensor or an isolated case because its only one side. One more thing to set that code it has to be fully warmed up and cooled at least twice. So the car has to do the same thing it did to set that code twice in two complete start up cycles. If it does that then it will turn the light back on. Hope this makes sense.
Last edited by LILWS6; Jan 2, 2007 at 08:20 PM. Reason: more text
do you have an aftermarket MAF? or other tuning? i had a granatelli and it worked great for 1k miles. i felt 15+ rwhp, but after that, my throttle was sluggish and i put the stock MAF back on and throttle was back to normal again. granatelli told me their MAF works with the diablo tuner only and had to be installed with factory tune otherwise the 2 won't work together. maybe you have done something similar to this? hope this helps
