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Full Version: Rough Idle
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Hey everyone, having some trouble with a rough idle on my '07 ISX and in need of advice. When I first crank the truck and at times throughout the day the truck will suddenly develop a pretty rough idle. The rpm's will jump up/down 50 rpm or so for a few minutes and then calm down to a regular idle. No check engine lights or smoke, truck pulls and drives fine. The temp gauge on the dash will also quit working at times, I have replaced the temp sensor twice but that didn't seem to help. I recently had the head replaced about 8 months ago and didn't know if this could be related. It almost seems that the ECM(also recently replaced) is getting a bad reading from somewhere and throwing it off but I could be wrong. Thanks in advance for any help!
Could be that metering or timing actuaters are sticking
is this a CM870 or CM871?.

Is it de-mandated(deleted)?. and if so, by who?.
Hey Rawze, it’s an 07’ 870 with no emissions
(02-10-2022 )rtjohnson1982 Wrote: [ -> ]Hey Rawze, it’s an 07’ 870 with no emissions

* if it is de-mandated, pull a copy of the program out of it and e-mail it to me for a review.

in the mean time, Adjust the overhead valves again and do an injector leak test on it to see if you have leaky injector(s)...
ref: http://rawze.com/forums/showthread.php?t...8#pid67948
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