jetaws6

iTrader: (3)

I think I have a bad ground connection because it sounds like I have electrical interference coming through the radio from my plug wires.

Under acceleration I start to hear a strange noise that sounds like a spark or a short and it sounds like it is coming through the head unit. It happens when the radio is off though as well.

I am really puzzled on this sound but I think this may be the solution. Where are the ground wires located and is there a way to test to interference?

wssix99

iTrader: (5)

Have you changed anything with the electronics or stereo? Has this been going on for a while? If not, then you alternator may be about to die?

Here's a good article on alternator whine (I expect this is what you are hearing) with probable causes: http://www.crutchfield.com/S-X9jsogt...ech/kb348.html

jetaws6

iTrader: (3)

Its not so much a whine its a nails on chalk board sound only not as intense as that and its not a constant noise its for a brief second over and over and the speed of it depends on the acceleration.

safemode

iTrader: (1)

If it happens when the radio is off, are you sure it's even coming through speakers? could be a bad pulley. Cold weather tends to make worn pulleys much more noisy, and their sound can be intermittant vs constant etc.

wssix99

iTrader: (5)

The speed of the sounds speeds up with the RPMs of the engine or the speed of the car?

jetaws6

iTrader: (3)

Rpms of the engine and only while accelerating past 3500 or so. Its not the speakers the sound is from the front of the car and its not a bearing in the trans because I just had that rebuilt and its still making the noise

wssix99

iTrader: (5)

I wonder if its in the valve train. Have you opened the hood and had someone rev the engine while you listen? (I assume you can cause the noise by revving the engine without moving.)

jetaws6

iTrader: (3)

no its only under load. I was thinking it could possible be a bent valve maybe or a spring. Its a h/c car but their is no ping or knock, it accelerates smooth so I eliminated that option.

wssix99

iTrader: (5)

I wonder if its some sort if bizarre vacuum leak? You said the sound is coming from the radio area and not through the radio speakers, right?

jetaws6

iTrader: (3)

I mean thats always a possibility until I pin point the sound but it sounds like its in the front middle of the car

wssix99

iTrader: (5)

Well the first thing is to confirm if its behind the dash or in the engine bay.

Suggest pulling the radio out of the dash and trying to re-create the noise. That might allow you to see/hear where its coming from if its in the dash.