sometimes, when my friend starts his car up, there is this loud annoying screeching sound for about 30 seconds coming from his engine area... i think its the belt. he took it to the dealer but they said it was just the condensation on the belt... is that right? he got the belt replaced about a month ago...

 

It needs to be tightened, that should fix the problem. Take it back to where you had it replaced and tell them to tighten them

 

I'm at a freakin loss with this (g35). My dealer hasnt blown me off on this, yet its still there. The AC compressor was replaced, all new belts, idler pulleys.. its still screeching when I feather the throttle backing out. Its not condesation.. at this point, I'm leaning toward the VDC sprockets.

The only downside is that I have to leave the car overnight to replicate it. The dealer has about 30 secs to diagnose. I've only given them about 3 opportunities to find it. We dont know whether its fixed or not til the next morning. I've talked to the techs and the service manager. They openly talk to me about it and we're not sure where to go now. I have an oil report, I dont have any main bearing wear.. I do think its external. Could be water pump or something. I've even used a stethascope (as has the dealer). I just cant find it.

 

but he says the belts were changed a month ago. I've gotten all new belts too. All the belts. That was the first thing the dealer did. His could be minor, could just need to check belt deflection... unfortunately for me, replacing and retensioning belts (two of the best dealers in the southern region), and the noise has persisted.. every morning, regardless of the weather, since last November.