Engine Runs Rough at Warm Idle
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Engine Runs Rough at Warm Idle
I have a 2003 150 with a 4.6. Lately after the truck is good and warm I've been getting rough idling/stalling.
Cleaned the IAC, MAF and throttle body
Changed PCV
Visually checked vacuum lines
Changed fuel filter
While I've noticed improvement overall I've now determined that at warm idle it sounds like something belt driven engaging and causing the engine to lag badly. When this happens I also notice a very high pitched belt noise (not very loud). It happens when the AC is on or off. Any suggestions?
Cleaned the IAC, MAF and throttle body
Changed PCV
Visually checked vacuum lines
Changed fuel filter
While I've noticed improvement overall I've now determined that at warm idle it sounds like something belt driven engaging and causing the engine to lag badly. When this happens I also notice a very high pitched belt noise (not very loud). It happens when the AC is on or off. Any suggestions?