2blklt4

Hi,
Got an `98 MN6 20000 miles.
When engine is on i have a light static noise sort of higher pitch static noise in left rear speaker, you can only hear it if volume is down all the way.

If engine is off and radio on, no static noise anywhere.
Any ideeas as to what it might be?

Thanx

Vassili

Could always unplug that speaker to see if it is the speaker or the wire. Then remove the other side speaker and plug it in the bad side. Just trying to eliminate possibilities...

molson

It's probobly the fuel pump....they were pretty noisy in the early cars

Navsafe

Don't put to much time, effort or money into it. The rear speakers do very little and the overall Bose system is poor anyway. Good opportunity and excuse to upgrade audio system or just disconnect the speaker. My .02

molson

I swapped my speakers and the noise is still there...

2blklt4

Now can i somehow hear the fuel pump thru the speaker? or fuel pump noise comes separate from different area?

molson

Check this link out..http://www.corvetteactioncenter.com/....php?qstId=238

Willsyb

Have a similar issue in my 04', but I'd describe it more as speaker feedback. Sounds like the same thing though......doesn't occur when engine is off....or if the radio is turned off, and engine is still running.

Did you ever find an answer?

Thanks.

BrianG01

if this were an aftermarket system, I would say that you ran your power and speaker wires too close together

Willsyb

I'm all stock.

Z28TOZO6

I believe there is a capacitor in the alternator that is supposed to alleviate that problem. Usually though you would hear that through all speakers if that were bad. the "whine" you are hearing is the engine running. It could be spark plug wires. Does it get louder if you rev the engine?

65GGvert

Another possibility is that the static is coming from the head unit. The amp in the head unit may have a bad component (bad filter, noisy transistor or IC). It happens to home and auto stereos all the time. You'll have to decide on whether to try to find a competent repair shop, replace the unit, or replace with aftermarket. You can buy a replacement (like on ebay) for between $100 and $200 dollars if it's an in dash cd, or less if it's a cassette. I bought a cd to replace my stock one for $109 plus shipping. I have a cassette unit that drives the 12 disk cd changer that I took out of my 03 AE with almost no miles on the car. Works perfectly and looks brand new. If you need that, send me a pm. My personal advice, if you can't hear it with the sound up, don't do anything. I seldom ride with the radio on and the volume down.
Just one other thought, if you go with aftermarket, remember the Bose speaker compatibility issues and wiring changes.
Sorry, I just reread your original post, you said no noise with engine off. It has to be picking up noise from the alternator circuit. Again, if you can't hear it with the sound up at all, I'd do nothing unless it got worse.

Willsyb

Always such great input and information on this forum. Thanks guys.

I think I'll leave my issue alone for the time being, seems like a lot of work for a minor issue. My only other thought is that my car is still under the factory warranty. Not sure I want to take it somewhere to have someone start replacing things though.

FU

Sound's like the speaker amp is on it's way out. Pull 'em out by the pair and get them fixed. Dr. Don's does a good job. Give them a call. he'll guide you through it.
http://www.doctordons.com/corvetteradios.htm

BATM4N

This sounds almost exactly like the same problem I had when I first got my vette.

I would hear that buzzing sound and some times it was worse than other times and seemed to be worse when the car was hot. The dealer had no clue what it was where I bought it so I went to the forum for help.

I first thought for sure it was the 12 disk changer. Then, I thought I had narrowed it down to the head unit. Shortly after I thought for sure it was the capacitor in the alternator. Lastly, I thought the left speaker was just going out.

Then I noticed a thread by Bill Curlee who was helping someone with a ground issue. When I saw where the grounds are located I thought that maybe water was getting to the grounds or the grounds had bad connections.

I stopped washing the car with a waterhose and switched over to a bucket of water and towel and stopped tons of water spilling over into the door jams where there is a ground close by.

The problem was so bad I just about ripped the whole bose system out, but once I stopped washing the car, soon after the problem disappeared, the Bose stereo system worked perfectly again and the problem has never back.

2blklt4

The problem is still there and learned to ignore it .
I think is the fuel pump given the GM bulletin that was issued in regards to early C5 `s.

Thre problem is that you can have exact same symptoms and totally different causes