Stereo & Electronics - Static coming through

I searched and couldn't find the answer, see here goes.....

My new 93Z that I just bought has a sony head unit in it, with aftermarket speaker. Somebody messed up when it was installed, because there is excess statc while the car is running. If I kill the engine but leave the stereo running, the static goes away. Turn the engine back on, static comes back.

whats the deal?

I searched and couldn't find the answer, see here goes.....

My new 93Z that I just bought has a sony head unit in it, with aftermarket speaker. Somebody messed up when it was installed, because there is excess statc while the car is running. If I kill the engine but leave the stereo running, the static goes away. Turn the engine back on, static comes back.

whats the deal?

sounds like a bad ground to me, either that or the RCA's are running right next to the power wire. Check the ground.

excuse my ignorance, but where is the ground suppossed to be?

I fix airplanes for a living, not car stereo's
:P

RCAs running next to power will almost never cause this, and if they do, there's another problem anyway. Put a noise supressor on the head unit power (switched, or both) and a capacitor should help, it doesn't have to be a big one.

You can try moving the RCAs, it might help, but having that amount of noise in a power wire is not normal.

Ground is anywhere on the car chassis, make sure there's no paint and that that it's sturdy. Don't go use some piece of metal that's connected via 2 spot welds. A common ground to use is the seatbelt bolts.

What dragonrage said is the best place to start. I didn't notice if you had an aftermarket amp running a sub though. Most grounds utilizing seatbelt loop is for a seperate amp running a sub in the rear. Something you may need to look at and is often overlooked is the factory ground wire behind the HU in this case your Sony. The stock ground is often either not sufficient of has deteriorated/come loose over the years. It could have also been pinched or something happen as a result of the install when putting everything back into the hole in the dash. Slide you radio out and leave everything hooked up. Turn on the radio, playing a cd so you don't get radio static, and see if moving the ground wire behind the factory harness affects the static your getting. Also, check tomake sure the ground has a good connection to the radio from the harness. It's a fairly easy process to do this and could find your problem. Good luck!!

check the ground, if not it could be EMI from some aftermarket plug wires