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Discussion Starter #1 (Edited)
I am trying to figure out why my Camaro randomly surges/bucks under light load. The rpms jump on the tach at the same time. Also it takes multiple tries to start when the engine is cooled off. I had transmission checked as everything reported ok. Here is a list of what I have repaired to try to fix this:

- new MAF
- new ICM
- new Coil Packs
- new spark plugs & wires
- Swapped with another used throttle body (since TPS is built in)
- tried a refurbished ECM to see if it would make a difference
- new knock sensors
- new cam sensor
- new crank sensor (fixed my stalling issues)
- new fuel pump
- new fuel filter
- new fuel pressure regulator
- repaired intake gaskets (since vacuum leak)

Two final notes: the voltage at the TPS is low both at idle and at 2500rpm. Secondly, bank 1 long term fuel trim seems to be running rich.
 

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Are there any trouble codes popping up (check eng lite)? It sounds like you are describing harsh missifre. The best thing to do is get a good diag scann of live data from PCM and see whats out of wack. And start there. You mentioned rich long term on bank 1.... Normally this means a rich condition, so check ignition and fuel delivery(injectors/regulator/miss fire etc). Jake
 

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Discussion Starter #3
Just thought I would post an update since this issue is resolved. I had two issues: randomly required multiple tries to start, and the surging/bucking issue. The two ended up being unrelated. I only really wanted the surging fixed.

Turned out it was the female terminals in the fuse box to one of the fuses had previously been probed. By this the terminals were stretched wide so the fuse was bouncing around and arcing when driving.

Secondly, some of my harness (to the ICM and throttle body) had been probed too with similar issues. However it was ultimately the fuse.
 

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Really glad you found that problem. THat could lead many into oblivion.

Electrical issues that mimic other conditions are the most difficult to resolve.
 
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