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YES... I just got it... THanks for the update!
Give me a minute so I can go through all of this info
Sorry for the delay!
I just had a chance to read what you have wrote.
WHat is the o2 sensor doing when this happens?
MAybe you just have a bad oxygen sensor?
WHat is the block learn at when the engine is at idle and off idle?
HAve you smoke tested the intake?
WHat about the fuel pressure regulator?
If you were to pull the IAC motor out and plug up the passages, does the engine idle better?
Are you saying that the engine idle speed on the scanner goes up and down but not the engine rpm itself?
WOW! THis is definitely an issue... maybe you have a bad computer??
I would scope the crank sensor to see if in fact the signal is erratic. If it is, then maybe you have a crnak sensor or a wiring issue. Also..just a thought... maybe the reluctor the engine speed sensor reads is a problem?? A quick check with a lab scope will be able to verify this for you.
But yet you have not scoped checked it yet have you?
In addition, there are two crank sensors and even one cam sensor. I would recommend to check them all. The computer will use all of these inputs to factor in engine rpm.
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