engine noise c400.4 help

docsnead

installed a pioneer DEH-P5800MP head unit and put db6750 in the front doors of my 02 avalanche.

Next I bought a C400.4 Carbon Series 4/3/2 channel Amplifier. When I first put it in I was getting engine noise through the speakers. So I thought it was maybe the ground wire and I unbolted it and used gas to clean the undercoat of the chassis then used sand paper and rebolted the ground. That didn't work so I started checking the RCA wires and when I would unpluged the front speaker RCA cables the noise would stop so I switch rca cables and unplugged the cable I thought was bad. I proceeded to ajusted the amp using only db6750 in the front doors man do they rock!

Today I put a new RCA cable on the rear speakers and Installed a brand new set of mmc6500 momo in the rear doors and when I went to test them my engine noise came back. Frustrated I put a jumper wire from the body ground to my chassis ground and that did not work either. If I unplug the either one of the RCA cables the noise goes away.

what should I do next ?

Thanks in advance ,
Keith

MacLeod

If youre getting noise with the RCA's unplugged then the noise is being induced into either the RCA's or from the head unit.

My first guess is that the head unit is the problem. Ive read a lot of complaints about engine noise in Pioneers.

One thing you can try, is to upgrade power wires to the HU especially if you had it installed somewhere. Those crappy 22 guage OEM wires aint the best. Run some 12 or 14 guage wire straight to the battery to the yellow wire from the HU and the same for the ground and then ground to a good location. See if that helps.

1996blackmax

Try running a set of RCA outside of the car to see if the noise is still there. There might be something along the RCA cable run that is causing this.


It is also true that there were some Pioneer units with internal grounding issues. Might want to look into that.

docsnead

Thanks guys I will check into the head unit to see if others have the same issues. My truck has onstar do you think that could have anything to do with it?
I ran a jumper wire from a solid body ground to the scew on the back of the head unit and the noise is still there when both rca cables are plug in but when I unplug either one and run with just one the noise disappears.
I was thinking of getting same monster brand RCAs what are your thoughts on those and which kind should I get?
I will straight wire the rca cables this weekend and see if that does it.

Thanks everyone for your input I will let you know how it goes.
best,
Keith

docsnead

rca routing was the proble thanks again.

MacLeod

Cool. Glad ya got it figured out. There is nothing more annoying than whiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiine while youre driving around.