We have a 2001 Pathfinder with the 3.5 L engine. The engine makes squeeks, like a bad bearing when you first start it, first 5 minutes, then it seems to subside. I had taken off all belts last summer, and felt each bearing. The tensioner pulley on the A/C side seemed to have a bad bearing. Replaced it and for a few months all was quiet. Then it returned, so I figured it must be the other tensioner pulley. Replaced it, and the noise is still there before warm up. Could it be the Water Pump? Temperature seems fine, and coolant loss is minimal, if any at all. The truck has 106,225 miles.
The belts do not do a screech when you first start in the cold, -very, initial startup, just as it ignites. It used to do this, and I just kept tightening the belt, until I think I burned out the bearings in the tensioners.
I have replaced both belts as well, but not recently. Any rule of thumb on how tight? Like, to be able to just twist it 90 degrees with a lot of effort?
Does any of this strike a common chord? Or if I'm way off, what should I check?
Best,
Bluemill