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2004 Ford F-150 Repair Question


Topics covered: Rpm, Surge, Air filter.
Mileage: 12,500 miles.

Asked on November 3, 2012

Ford F-150 Rpm Problem

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.
Avatar Asked by joey_37748

Answer

Replied on 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.

Tiny Answered by hmac300 (expert)
17,927 answers provided
Replied on November 18, 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 Response from joey_37748
1 question asked
Replied on November 18, 2012

k&n filters can cause problems if they are oied to much so make its not

Tiny Answered by hmac300 (expert)
17,927 answers provided