AC vibration?
 

My car has developed a vibration that sounds like its coming from the center of the dash between 1500-1700 RPM's. I suspect its one of my accesories because when I remove the belt and run the engine - no vibration. Waterpump is new, damper is new, alternator seems OK (G3), power steering not original, smog pump gone. The AC works great, but the compressor is starting to make a grinding sound when on. Has anyone experienced this before? I've heard other brand cars compressors squeal when the clutch starts going out. Do mustangs grind instead?

Re: AC vibration?
 

Just had a friend go through this problem in his Jeep.
After all his hunting and replacing, it was the belt tensioner.
I didn't even know they could go out.

Then two days ago, my dad called and told me he had to replace the tensioner in his truck.

It's something to look at.

Re: AC vibration?
 

I replaced the tensioner pulley (forgot to mention that one). Even though the old one was sounding rough, it didn't make the problem go away.

Re: AC vibration?
 

Tensioners go bad all the time, we change several a week.

Does it vibrate with the a/c off as well as on??

The a/c compressor will make a "grinding" noise as it goes bad.

How about the water pump?? When you turn it by hand, how does it feel, sound, etc.

Re: AC vibration?
 

The AC compressor does grind while on. I was wondering if it eventually causes a vibration once it gets bad enough to do it while the AC is off. The water pump is brand new. I guess I might have to wait until it gets so nasty that its obvious where its coming from. I can't hear it under the hood while the engine is running - too loud. Each accesory spins fine by hand - for now. Is the grinding in the compressor a bad clutch or does the whole thing need to go?

Re: AC vibration?
 

Compressor is bad. Sorry...