Engine Noise, US Acoustics 5050 Amplifier

I recently installed my new US Acoustics 5050 Amplifier using 8 gauge cable for both power and ground, but I am experiencing engine noise that is becoming very annoying. My ground cable is approximately 18" long and is grounded to a rib under my seat (yes, I sanded all the paint away from the surface) and my RCA's and speaker wires do not come into contact with either the power or ground cables. Should I re-ground the amp in another area or is there another fix out there that I can accomplish?

Thanks for your help.

Razorbacx

To start with change your ground location, and check your rca's for any pinches breaks etc. Also when you say your rca's and power don’t touch each other are they run on opposite sides of the car? Also what do you have your gains set at?

bberman1, my RCA's are ran down the center thru my console and my Power is ran down the right side of my car. My RCA's are in perfect condition and are not pinched. My Gain is set dead center of the adjustment knob, not sure what the actually number is though. I will relocate my grounding point and hopefully that will solve the problem and possibly re-route some wires to ensure that they are not touching anything that they should not be. How short can my Ground be? The reason why I ask is because if I turn my amp 180 degrees I can further isolate the wiring. I'll also check my gain to ensure that I did not inadverrtently move it when completing my installation.

Thanks for the response!

Razorbacx

My remote wire is ran along side of my RCA's. Does this present a problem? I have a Pioneer Premier DEH-550MP (MP3 Player). I am running no extra components. My system is rather simple. I have JBL 3 way 6.5" speakers installed in the front doors and MB Quart 6x9's in the rear deck. I had a smaller amp installed before I got my US Acoustics and had no Engine Noise, but I think because of the stronger pull of my new amp that it has got to be my ground. I will move it this weekend and let you know if that fixes my problem.

Thanks for all your help bberman1!

Kind Regards,

Razorbacx

Don't worry about the routing of the remote turn-on lead.  That wire just carries DC current, so it cannot induce noise into the RCA cables, even if you spiral-wound the turn-on lead around the RCAs.

The most important question that I haven't seen addressed is what kind of "engine noise" are you getting?  Is it an alternator whine that varies with engine speed?  Is it a popping/clicking sound like the kind you get from unshielded spark plugs?

I agree that the ground location is the most likely problem.  It doesn't matter as much how long the ground wire is - what's important is that you have a clean connection to a good ground point.  Try disconnecting the ground from under the seat and temporarily run a length of 8-gauge ground wire from the amp directly to the negative terminal of the battery.  Run it out the car window and under the hood - it's just a temporary connection.  If your noise goes away, you've found your problem.  If your amp is bolted to your chassis, make sure you unbolt it and lay it on something non-conductive before you do this.  If your amp chassis is touching ground, it's possible to get a loop, no matter how good the main ground connection to your amp is.

One other thing to try if re-grounding the amp doesn't work.  If you have enough slack in your wiring harness, try pulling the head unit out of the dash to make sure the head unit's chassis isn't grounding through your car's body.  Since you said your system was noise-free before installing your new amp, I don't think you're getting ground loops through the head unit, but I've seen it happen.

Scott Gardner

Durwood,

Thanks for the additional info! I really appreciate you taking the time to do so.

The engine noise that I am getting is a "WHINNING NOISE" and does vary between speed, so I agree that it has got to be the ground. I have been so busy here at work and home that I have been unable to correct the problem, but plan on doing so in the next week.

Once again, many thanks to you and bberman1!

Happy Holidays!

Razorbacx