Down on power + a backfire
Down on power + a backfire My car has been down on power for awhile now, and i'm not sure what's going on. I know this because my friend's stock 00 M6 T/A keeps up with me from a roll, and I only trapped 106mph in the 1/4 last time at the track.
The car runs and drives normal, good throttle response, no missing, etc. It doesn't matter what rpm I'm at, my friend's T/A runs even with me through all the gears. The only other symptom is the car will backfire loudly (enough to feel the shock) about 5 seconds after letting off from a WOT run. It will do this if I let off and coast in neutral or if I decelerate in any gear.
No codes are thrown, the TR-55 plugs have ~15k gapped at 0.050", and the wires are less than a year old. 7 of the plugs all look the same; not sure about #8 as I didn't pull it when checking for bent pushrods. Only thing I can think of is there's from a cylinder not firing. Any ideas? thanks
Jason
The car runs and drives normal, good throttle response, no missing, etc. It doesn't matter what rpm I'm at, my friend's T/A runs even with me through all the gears. The only other symptom is the car will backfire loudly (enough to feel the shock) about 5 seconds after letting off from a WOT run. It will do this if I let off and coast in neutral or if I decelerate in any gear.
No codes are thrown, the TR-55 plugs have ~15k gapped at 0.050", and the wires are less than a year old. 7 of the plugs all look the same; not sure about #8 as I didn't pull it when checking for bent pushrods. Only thing I can think of is there's from a cylinder not firing. Any ideas? thanks
Jason
Last edited by Camaro99SS; Jun 14, 2007 at 09:56 PM.
I fogot to mention the car does blow out some black smoke at WOT. In the current tune, the car registered 12.8-12.9 air/fuel on the dyno the whole pull about 1.5 years ago.
Jason
Jason
Well I put new plugs in this past Sunday (TR-55's @ 0.060") and broke the coolant temp sensor by plug #1. I put a new Delco unit in, and now I have another issue. The car seems to run fine part throttle (haven't gone WOT yet), but the guage doesn't work, the fans run all the time, and I'm throwing code P0118, high voltage.
Another interesting thing is that the car would never start with the original sensor unplugged, but with this new sensor, the car runs regardless. I verified with the dealer I got the correct part, and I even tried another sensor from another parts store. What gives?
Jason
Another interesting thing is that the car would never start with the original sensor unplugged, but with this new sensor, the car runs regardless. I verified with the dealer I got the correct part, and I even tried another sensor from another parts store. What gives?
Jason
Trending Topics
P0118 indicates a bad sensor. I know it sounds weird but either 2 new sensors are bad or the plug wires for it got messed up. Use a voltmeter to see if you are getting a reading. Google P0118 and you'll see what I mean.
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