5th Gen 3.1l LIM gasket replacement due to high idle
#31
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Does your scan tool have an option for reading IAC counts? If I remember right, this represents what the pcm is trying to output to the IAC. I believe the range is 0 (closed) to 255 (full open, although on many TBs it fully uncovers the entire passage well before that).
If so, it would be useful to monitor that from startup and see if the increased idle corresponds to a spike in counts. It should start fairly high but slowly begin closing. If it spikes up when your idle jumps, then you've eliminated one of the three possibilities as you will know its a pcm commanded spike.
If so, it would be useful to monitor that from startup and see if the increased idle corresponds to a spike in counts. It should start fairly high but slowly begin closing. If it spikes up when your idle jumps, then you've eliminated one of the three possibilities as you will know its a pcm commanded spike.
The bit of live data I can get after warming up says
Ign adv: ~ -18 degrees
Long term trim: -4.7
O2S11: bounces from ~.390 to ~.800
O2S12: bounces around .200 plus or minus .015
Short term trims are about 1.6, fell to .8 as I typed this
I can add fuel now and it will rev up so it’s not running as rich before. The RPMs climbed up to nearly 1700 as I typed this and back to ~1000 after shutting it off and cranking it back up.
#32
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Well I finally got a hold of a smoke machine. Flooded the intake and found no leaked in the engine bay but a massive Evap leak under the car. Patched that all up and it holds well, but it still runs the same. Idle that starts a little high and goes up. Thinking about picking up a cheap ecu, hopefully one that won’t have to be reprogrammed, and see what happens.
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