whine noise

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 about a pint low as it has a leak in the pressure hose, but still pink and the power steering fluid is at the add 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.

Reply to
steven mantas
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If the noise is made by something being driven by the belt, then a simple way to test it is to ease up on the belt tensioner while the engine is running. If the sound changes or disappearscompletely, then it is probably the alternator, water pump, power steering or the tensioner itself. The AC Compressor I think you'd be able to tell if it was making noise just by standing there & listening.

Another test is to take a long socket extension and put in on the back of the alternator near where the bearing is. A Whirring bearing noise will travel right up the bar into your eardrum. KInd of like using a stetha scope, which they do have for cars. Same can be done for the Power steering pump & maybe the water pump, if you can get to it safely.

With the engine off you can also slip the belt off and spin each pulley by hand checking for drag or any excess up & down movement. Pulleys should spin freely.

Use caution when loosening the belt tensioner while the motor is running, make sure your tool has a good grip and don't slip.

Maybe have somebody else loosen it while you do the listen.

good luck.

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~297,525 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan
Reply to
Harry Face

My money is on the alternator. After owning 3 late 80s early 90s FWD GMs, and going through 7 or 8 alternators, there is no mistaking the noise of a bad alternator.

Steve

Reply to
Steve Mackie

Thanks.....come to think of it, the alt gauge seems to be overcharging a brand new battery....it's reading is at around 16.......I am told a normal reading should be around 14, is this true?... could I leave it like that for a while or is that too much and could do electrical damage?

Reply to
steven mantas

I vote Alternator

Reply to
Tim or Linda

I believe anything between 12V and 16V is acceptable. However, I wouldn't leave it. As anyone in here can attest, when an alternator goes, it could leave you stranded.

Steve

Reply to
Steve Mackie

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