2002 Explorer Engine Chirp

I had a similar problem on my 1997 Explorer although mine started a week after I bought it new.. Had it back to the dealer a couple of times without any permanent resolution. Went through about the same things on your list. My chirp/squeal would come and go and always seemed to go whenever I took it in.

Anyway, to make a long story short, I ended up stopping immediately as it was happening, threw open the hood and looked and listened carefully. What I found was that the serpentine belt was riding just enough off center of the idler pulley that it was squeaking on the edge of the pulley. Temperature changes and engine speed would make it come and go. I thought about shimming under one edge of the mounting flange but it was just too difficult so I ended up filing the surface of the flange were it mounted to the engine block just enough so that the belt ran exactly in the middle of the idler pulley. Temperature and RPM changes no longer made the belt ride too close to the edge. I never had the noise again after that.

Look very carefully at the belt position on the idler. Make sure it's dead-center on the pulley.

Hope this helps. Don

---------------------------------------------------

Not exactly a chirp, but there is a TSB that is titled something like "Engine Groan", which I have experienced. IIRC, it has something to do with the air conditioner clutch.

Bill

Update on the situation:

- There is now a TSB for the water pump pulley. So add that to the replacement list.