Vince31501

Hey everyone I have 1994 sc400 love it great car. I recently got a new pioneer touchscreen headunit, put in by best buy cause free installation. Anyway I did that and the guy at best buy told me that he would need to bypass the amp or have me buy a new amp, I just wanted to hear from you guys what thought. The radio is in but there's a whining noise that is in tune with the engine so if I rev it gets louder.

TLDR: NEW pioneer headunit installed, there is now a whine and I was told to do an amp bypass or buy a new amp by best buy

thank you guys

xCWolf

So that engine noise is alternator whine. could be a bad ground, could be power wire picking up noise. Tough to diagnose remotely.

Did you end up putting in a new amp? if so than the power wire for the amp is probably run on the same side as the signal wires and causing the noise.

AFAIK the amp does need to be bypassed as there's no reasonable way to interface into it.