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Rough Idle - Printable Version

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Rough Idle - rtjohnson1982 - 02-09-2022

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!


RE: Rough Idle - Running rough - 02-10-2022

Could be that metering or timing actuaters are sticking


RE: Rough Idle - Rawze - 02-10-2022

is this a CM870 or CM871?.

Is it de-mandated(deleted)?. and if so, by who?.


RE: Rough Idle - rtjohnson1982 - 02-10-2022

Hey Rawze, it’s an 07’ 870 with no emissions


RE: Rough Idle - Rawze - 02-11-2022

(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?tid=7747&pid=67948#pid67948