Mechanics

FORD F-150 RPM PROBLEM

2004 Ford F-150 • 12,500 miles

I have a Ford F-150 4.6 V8. The RPMs has started to surge up and down while driving at a constant speed. If I take it out of overdrive it doesn't surge. It starts fine and no missing. Changed the fuel filter today. No change. I have a K& N air filter. I also cleaned it with their kit. No change.
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Joey_37748
November 3, 2012.




Check fuel pressure and scan for codes. Clean throttle plate on both sides with choke cleaner as well as iac hold if you have one.
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Hmac300
Nov 3, 2012.
I took the truck to the ford dealer. They hooked it up and no codes came up. They couldn't find the problem.
I changed out the fuel pump module above the spare tire. This did not help. I drove it a couple miles and the engine died when I pulled into a parking lot. It started right up and I drove it home. It died when I pulled into the driveway. It will restart, but while idling, the rpms will raise and drop by 100-200 rpms. It used to ony surge when I was driving in overdrive at a constant spead.

I haven't tryed cleaning the throttle plate yet, but plan on it over the holidays.

Tiny
Joey_37748
Nov 18, 2012.
K& n filters can cause problems if they are oied to much so make its not

Hmac300
Nov 18, 2012.

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