Rough idle when warm?

2008 FORD RANGER
184,000 MILES • 3.0L • 6 CYL • 2WD • AUTOMATIC
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NATE083.0
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Rough idle more so when warmed up. Fuel pump, filter, coil pack, plugs and wires have been changed. Pulls good when driving just rough idle. Also, I've cleaned the throttle body and MAF sensor as well as cleaned the IAC.
Apr 6, 2025 at 4:04 PM
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STRAILER
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A rough idle can be caused by low compression on one cylinder/leaky intake valve or a fuel injector going bad, I would remove all spark plugs and look for one that is dark in color, this will be the cylinder having the issue. Also, we should run the codes to see if any are stored.

These two guides can help:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

and

https://www.2carpros.com/articles/repairing-engine-rough-idle-issues

Vacuum leaks are famous for causing a rough idle as well.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please go over these guides and get back to us.
Apr 7, 2025 at 11:30 AM