2004 F150 5.4 - Ford Forums

pokey36 · 03-21-2009, 20:21

While in idle the engines makes a pecking noise. I changed the oil and it stoped for about 15 min. Thanks

**360ci** · 03-23-2009, 17:35

Peck...as in a tick noise?
What's the mileage?

You may be experiencing engine knock, which can be disastrous over prolonged periods. I'd get a tune up done, with new plugs for sure. If the noise rises with engine speed then it could be a valve train problem. As a test for pre-detonation try running ten gallons of 91 octane once your desperate for fuel, this is providing you currently run regular (87octane or lower). The higher octane burns differently but a good tune up can also correct any timing issue you may have.

jr54lt · 04-20-2009, 09:32

My 2004 5.4 liter has the same problem. It sounds like a valvetrain issue. It only occurs when the engine is warmed up and it goes away above 1600 rpm. Could this be a bad lifter or maybe an oil pressure problem?