squeaking from engine

Have a 1994 3.8 litre transport with 180,000 miles on it. Replaced alternator, tension pulley, and water pump. Does not make noise when serpentine belt is off. Those before mentioned pulleys did have some noise to them. The noise is a squeak that does increase with RPM increase. I have read in other posts that harmonic balancer pulley could be at fault.Noise is coming from the same side of engine as pulleys and did get better as engine warms up but is extremely annoying.:mad: Do not have any problems with performance other than the occasional stall due to other issues that do not set off the CEL. Any suggestions or how to diagnosis would be greatly appreciated. :eek7:

Almost 2 years ago, I had a similar funny noise that I could not easily isolate on our 95 transport 3.8L. At that time, I was unable to keep working on it.
I took the van to Firestone. They told me they needed to replace the water pump. I just replaced it about 2 months prior for leaking. They replaced the pump and no change.

The problem was the harmonic balancer. The rubber tore for the balancer. However, there was some vibration as the rpms were increased on the motor.
I have never seen a failed balancer prior to this time....a lot of years

Does the squeak stop when the A/C is turned on?.....test but verify that the a/c clutch actually engages (low temp/low refrigerant pressure may inhibit a/c operation). Fact is that the free wheeling bearing of the a/c compressor or the clutch itself commonly generates squeaking ..and that disappears as soon as clutch engages beause it stops relative movement.
Bearing/clutch can be serviced in place from the wheel well without removing the compressor but normally requires special servicing tools..

What about the belt? Does noise go away if you spray silicone on the belt while the engine is running?

It turned out to be broken a/c mounting bracket. Ended up searching this forum and found a post that let me know how to bypass a/c option on engine with a small length serpentine belt. Doesn't make any noise now. Sorry for the late update. Still have to pick up bracket from welding shop for the second time. It didn't break at the previous welds either to no amazement form welder guy. I believe it was a olds egine without a/c option. Could not find this option anywhere on the internet but did find it on this forum. You guys are the greatest. Thank You!