OK. so i have a 02 f150 XLT FX4. this has been goin on for like 7 months and im tired of it. there is a sqeaking noise coming from motor when it idles. its not belt, idler pulleys. i changed both of those. i think from left/passenger side of the motor. it STOPS when i rev the motor slightly.i cant really describe the sounds but its a sqealing sqeaking noise. it happens when the truck is idling and when i rev it a bit it quits.
HELP!!!!

 

I'm guessing it's the alternator.. Have that checked

 

yeah i probably will but it sounds like its coming from the valves on the left side of the motor. i could be wrong.

 

Ya because I know my truck does/did that and the mechanic said there is 3 things that usually squeak on an engine. Alternator, air conditioning compressor, and another thing that I can't remember but it was on the driver side. I am really confused now though because I took it to the shop and they oiled the belts up.. Stopped squeaking for the day. Ok good. Next morning started to squeak.. Ah ****. So leave it. Then I thought my brakes were going out. Tell the mechanic ok can you change the brake pads? Sure. Get it back he said the brakes were fine but there was alot of dirt and rocks in them. Ok do drive it home and stops squeaking. Great it was just my brakes.then next day she squeaks again. Still squeaks for me so I just left it