Engine noise through speakers
 

I recently picked up an R53 3 weeks ago and love everything about it except for the damn engine noise that goes through the speakers. The previous owner had upgraded the amp from the harmon kardon one that tends to go out according to other R53 owners. He swapped it out with an aftermarket one, lengthened the speaker wire, and left the stock alpine radio. So theres engine noise and static noise coming in through speakers. It also happens when i turn the headlights on, press the brake and use my blinkers. I recently took out the stock stereo and swapped it out with a new Pioneer x6800bt and hooked it up to the existing amp. I grounded the new stereo to the chassis, I switched the ground to a stock bolt and shortened the length of the ground from the amp. I still have engine noise. My next step is to gut out the interior and run speaker wires individually to the existing amp, a new remote wire from the stock amp to the stereo and see if theres any interference with that. If theres still engine noise with that i will hook it up directly to the stock stereo.

Has anyone had a bad case of engine noise? Let me know thanks.

Wire in a ground loop noise isolator first before you go tearing everything apart...

http://www.crutchfield.com/S-6dFRBrL...PAC-SNI-1.html

I'd give that a shot first. My R53 has a similar issue but maybe not as pronounced as what you're describing. Mine is most noticeable when listening to talk radio like NPR. I don't drive the car daily so I've decided to ignore the issue for now.

I already bought a ground loop isolator and connected it through the RCA's. It helped a bit to reduce the noise, but its still there.

I would see where you have it grounded. I would ground it to the radio ground for the amp or a another place that might reduce the feedback noise.

Might try a filter. It'll help reduce the engine noise through the speakers. I had this issue with a nav set up in a different car and it was pretty annoying. Good luck!