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Strange Noise


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Today noticed a strange noise coming from somewhere between transmission and the left headlight when I turn ifnition ON ( the engine is OFF). Kind of short rubbing noise! :blink: What can activate there by turning ignition ON? Any motor, pump, actuator? It is not ISC motor.

The noise drives me nuts, have had enough problems to fix. :angry:

Thanks for any suggestion.

The saddest thing in life is wasted talent

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adallak,

The only things that come to mind are the anti-skid motor on the brakes and the left cooling fan for the radiator.

You could try to isolate the cause by finding and pulling the associated fuse or circuit breaker for whatever you suspect could be causing the noise.

Good Luck, Britt

Britt
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adallak,

Sorry for the nomenclature (anti-skid motor). I was having a brain fart & couldn't think of the proper term for the BPM.

There is a motor in the brake pressure modulator valve (BPM). The modulator valve has a valve relay and a pump motor relay under the cover of the BPM.

Something you could try, if you still have trouble finding the source of the noise is to get a mechanic's stethoscope. Use the probe to touch different items to see if it is making the noise.

There is a solenoid in the EVAP canister. However, I doubt that it could make the sound that you describe.

If there is something wrong with either of these systems, it should be pulling some kind of code.

The EVAP, BPM and the EGR solenoid all are hot in "Run". (Key on.)

Good Luck,

Britt

Britt
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Britt,

thanks for the clarification. The noise is gone (at least today I did not get it). Could a low gas make fuel pump whine - thump like that. I filled it up and no noise. Another possibility (i wish I were wrong ) the transmission. I powerbraked it the day before really hard and probably overheated it. Does anything in transmission activate when you turne the ignition on (motor off)?

Despite I know the pump in the tank sometimes you really cannot point the real sourse of the noise.

The saddest thing in life is wasted talent

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Sometimes my air ride compressor comes on with the ignition ON, to level out or who knows what... but the noise is a little strange if you have never heard it before...

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adallak,

I don't think that it was your fuel pump. If the fuel is low enough to draw air, it will usually not start, let alone drive to the gas station.

I don't believe that it is your transmission either. It could have been the air compressor for the rear shocks, but that is located under the car just in front of the trunk.

You said "rubbing noise" in your first post. Did you mean "running noise"?

Try to give a more detailed description please.

Britt

Britt
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Britt,

It was kind of short rubbing noise like some electrical motor or pump makes not regular noise because of overload or something... Only thin g I know i never heard it before.

Joe M, the noise you ger everytime you turn ignition ON is some kind og compressor (may be rear shocks) . It does not start right away . It usually takes some 10 -30 seconds before it runs gor a few secs. I really do not know what is the noise the fuel pump makes. Actually I could confuse that air compressor with the fuel pump.

Whatever... the noise I had yesterday was definitely something unheard before.

My transmission fluide is not dark just discolored (brownish) and smells a bit differently than the fresh one. I hope it is not burnt since was told you can miss the burnt odor. Fresh ATF is bright pink and smells like kerosine to me.

The saddest thing in life is wasted talent

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adallak,

Well, I'm stumped. I can only think that it could be a radiator fan rubbing.

As far as your transmission fluid, it sounds like you are due for a change. If it is turning brown, I would change it right away. If you have the N* don't forget the internal drain plug that has to be removed to drain the side case. (Don't forget to put it back either!) ;) I don't know if the 4T60E (with a 4.9 engine) has an internal drain plug like the 4T80E or not.

Britt

Britt
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I don't think they turn on when you turn the key on, but its a possiblity that one of your cooling fans are making noise, I had one go bad on my 91 and it wobbled. Maybe if your AC is on, the cooling fans come on with the key. Just a thought.

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I don't think they turn on when you turn the key on, but its a possiblity that one of your cooling fans are making noise, I had one go bad on my 91 and it wobbled. Maybe if your AC is on, the cooling fans come on with the key. Just a thought.

Scotty and Navion ,

It was not a cooling fan - they are fine and besides the temp was below 180 , so no fan.

As far as ATF is concerned I think the color chenges afterfour years and 50.000 miles.

Or may be I am just too optimistic? :blink:

The saddest thing in life is wasted talent

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It sounds like the ABS acumulator from your description of the location. My '93 STS does this from time to time, especially in warmer weather.

Is it an intermittent "Brrrpp-Brrrrpp-Brrrrrrpp" sound?

If so, that's it. The ABS is a very high pressure system that 'charges' at startup as necessary to equalize the system. The more equalising needed, the more cycles you will hear. Mine's been doing it since I got the car a few years back now. It comes and goes, so I try not to let it bug me too much, as it is normal to a point...That point being excessive charging means a leak some where, and the accumualtor needs replacing.

Mine just started up again the other day, after a long winter pause..Still, it comes and goes so, I'm not worrying. If it gets constant, well... time for a change. Not to bad for a 12 year old car if that's the case.

I'm trying to remember some 'research' into the cost a year or two back, and 800 bucks, comes to mind for some reason...

'93 STS.. opened, dropped, wide...fast.

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It sounds like the ABS acumulator from your description of the location. My '93 STS does this from time to time, especially in warmer weather.

Is it an intermittent "Brrrpp-Brrrrpp-Brrrrrrpp" sound?

If so, that's it. The ABS is a very high pressure system that 'charges' at startup as necessary to equalize the system. The more equalising needed, the more cycles you will hear. Mine's been doing it since I got the car a few years back now. It comes and goes, so I try not to let it bug me too much, as it is normal to a point...That point being excessive charging means a leak some where, and the accumualtor needs replacing.

Mine just started up again the other day, after a long winter pause..Still, it comes and goes so, I'm not worrying. If it gets constant, well... time for a change. Not to bad for a 12 year old car if that's the case.

I'm trying to remember some 'research' into the cost a year or two back, and 800 bucks, comes to mind for some reason...

Bob D,

The sound was sort of oouuuppp (like a wiper on a dry windshield)... just a single for 2 seconds. Let's see if it comes back some day. My ABS never did any noise. Brrrppp-Brrrpp sound rather like ISC motor adjusting itself for the next start.

If it is not some pump inside transmission I really do not care much. I just tried to remember something unusul with the before that noise came and it was a series of pretty hard powerbraking for diagnostics purposes (ten times @ 2000 RPM for 30-60 seconds each with a few seconds intervals...).

The saddest thing in life is wasted talent

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