I have a 1994 Buick Regal with the 3800 V-6 and the 4T60E transmission. This car has 46000 actual miles and was purchased from the original 85 year old owner who is now deceased.

The problem I am having is this noise from under the hood which I cannot pinpoint.

It's a constant higher pitched humming/whineing noise that changes pitch when the engine is revved. The more you rev it the higher the pitch of the noise. It also changes pitch when it's driven and it changes gears.

The pitch gets higher as it's about to change gears and then low again according to the speed I am driving. Like I said it will do this in park also and changes pitch as I rev it up.

Trans fluid is pink and power steering is at the full mark mark.

I just got this car and was wondering if this is something on the engine such as a tensioner pully, alternator or is it something in the transmission itself. It shifts smooth and normal.

Any info would be appreciated.

There are a couple of diagnostic procedures you can do. If you have a long screwdriver,(~2 feet) while the engine is running, carefully put the blade on a nonmoving part of the alternator, tensioner, water, and PS pump. compare the sounds, and if one is not a steady hum, it could be problematic

You can also remore the belt, and turn the said pulleys by hand, listening for any abnormal grinding

definately lot transmission related. Power steering pump, Alternator, water pump, or idler wheel/tensioner is what's making the problem. Before anything check your power steering fluid and make sure it's full. - that could cause a whine.

Recently, I had a similar problem with my 1999 Regal LS. After a few miles of running and warming up the engine, I noticed a high pitch whining sound coming from the automatic transmission. The gear shifting and downshifting was very harsh. After turning it off and re-starting it worked fine for a while. My idle was erratic and the car would hesitate or stall intermittently.

Then my service engine soon (SES) lamp illuminated. I took it to Autozone where they ran an ODB-II Code Reader for free and it showed a DTC of the MAF (Mass Airflow) sensor being defective. The transmission references off the MAF sensor through the ECM module. It is located on the top of the throttle body right after the air cleaner assembly. It has an electrical connector with 3 wires. I disconnected the sensor plug and it ran fine....no problems with the tramsmission whine, erratic idle/acceleration, etc. The theory behind why it works is because the ECM went to limp home mode and switched to referencing RPMs instead of the signal from the MAF sensor. Some defective MAF sensors may not give you a SES light but most will.

Autozone had a Cardone MAF sensor for $135 plus $87.00 core exchange
and special order but I found one at a local salvage yard for $35.00 off a wrecked 1999 Regal with only 5K miles. I hope the info helps you and others.

I have the same problem with my 96 regal 3.8. Whines even in neutral. How did you ultimately resolve this issue?
Any info would be appreciated.[/QUOTE]