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Old Jul 23, 2011 | 02:10 PM
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I just bought this 2000 trans am t56 car. It has a few issues i have been dealing with .
when i first got it I had some DTC codes codes where bank 2 lean and ignition coils a and C ... these codes came after i cleared the original codes that sad bad 02 heater sensor and bad 02 circuit etc etc.. I went ahead and replace both 02 sensors on bank2 and replaced the plugs and wires....

now the car has not thrown any codes at all but is very apparently misfiring still. not nearly as bad as it was .. any info or help will be greatly appreciated.
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Old Jul 23, 2011 | 04:20 PM
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How do you know it is still misfiring? Codes?
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Old Jul 23, 2011 | 05:26 PM
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no codes. but while driving you can feel it while accelerating the car kinda stumbles but still accelerates and there is an apparent loss of power.
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Old Jul 23, 2011 | 05:30 PM
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Are your RPM's stayin stable or are they fluctuating?
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Old Jul 23, 2011 | 05:33 PM
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it idles just fine. stays steady. if i blip the gas while sitting still you can here it missing a cackling. will sometimes pop out the exhaust ..but then returns back to a steady idle
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Old Jul 23, 2011 | 05:43 PM
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Hmmm, is everything plugged in properly for the main wiring harness?
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Old Jul 23, 2011 | 06:05 PM
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i checked everything. didnt see anything unplugged.. the car has been sitting for atleast a few months also ( i just baught it got a stupid good deal so worth it for me to go through this haha) any chance the gas could be bad or fuel filter? would that cause the symptons...? im thinking i just havent driven it long enough for it to throw a code again to tell me where its mis firing. but the codes it had this morning before replacing everything said the ignition coil A and C where malfunctioning. i figured this could have been caused by the bad o2 or even bad plugs/wires.
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Old Jul 23, 2011 | 06:14 PM
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Contaminated fuel is a real possibilty. Change the fuel filter, fill up with fresh fuel, and put some fuel system cleaner.
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Old Jul 23, 2011 | 06:17 PM
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where is the fuel filter located? also the car has a half tank in it already. could i just fill it up the rest of the way and add cleaner or should i find some way to drain it?
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Old Jul 23, 2011 | 06:38 PM
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Originally Posted by runnin13s
where is the fuel filter located? also the car has a half tank in it already. could i just fill it up the rest of the way and add cleaner or should i find some way to drain it?
If the car is running well enough to use the fuel I would just add some cleaner and fill it up. If you can drain some that would speed up the "recovery" process. The fuel filter is usually located on the fuel lines that run adjacent to the frame between the tank and the engine.

This link might help.

http://www.installuniversity.com/
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Old Jul 23, 2011 | 08:50 PM
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Drain and replace the filter then add gas and have fun!
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Old Jul 24, 2011 | 01:14 PM
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ok ,,, i replaced the fuel filter , cleaned the mass air and the throttle body .. .. i took it for a drive and it threw a few codes.. Ignition coils A, C, E, G. and mass air sensor ,, i then realized that i didnt hook the mass air back up haha... hooked it back up cleared the codes and have not got any codes back as of yet. ... what could cause all the ignition coils codes?
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Old Jul 24, 2011 | 04:33 PM
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Do you have the code numbers?
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Old Jul 24, 2011 | 08:30 PM
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Well I think I may have found the culprit. The main harness that connects to the coils I traced it back and found a previously repaired wire I took it apart and soldered it up. Runs like a champ no misfiring or codes as of yet.
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Old Jul 25, 2011 | 08:51 AM
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Originally Posted by runnin13s
Well I think I may have found the culprit. The main harness that connects to the coils I traced it back and found a previously repaired wire I took it apart and soldered it up. Runs like a champ no misfiring or codes as of yet.
wiring lol that little crap
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Old Jul 25, 2011 | 03:52 PM
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Good for you man, wiring is one of the scariest problems to have with a car. Give me a fould plug, burnt plug wires, bad O2 sensor any day over tracing some bad wire...yuck.

Glad you found the culprit! Let it be a lesson - no shortcuts with this car!
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