I just installed an aftermarket stereo using the factory amp and speeakers in a 92 sc400...problem is ....there is an annoying whine when the engine is running that wasn't there with the factory stereo...I used a scoche interface to adapt the wires ...any ideas on how to get rid of the ignition noise ?

 

Find the ground wire (usually black) coming out of the aftermarket HU and re-route it to a better ground point. Use a test light to make sure. You could also have a bad HU and/or scoche harness.

Jim

 

You should also get a noise filter....try Crutchfield.com