im running a kenwood x692 deck, and a pair of kicker ds650 speakers, i keep getting engine noise and cant get rid of it, so far i have swapped amps, swapped rca's, put a noise filter on the hu, changed grounds multiple times, re ran power leads and rcas to have them far away from each other, tried using a different set of pre outs on the back of the hu, and i still cant get rid of it. any ideas?

 

where is the power supply attached?

 

the power lead for the amps comes off the battery through an anl fuse through the firewall and under the drivers side kick panels, then it goes to a distribution block, then to the amp

 

I had the same problem with my truck, after i shortend up all my grounds, and added a few extra grounds from the batt to the engine and chassi it went away. Also dont run your rca cables along the same side as your main power cable for your amps, run the power wire all by its self on one side and any other wires on the other. good luck

 

Turn the gain on your amp down and if you can, increase the voltage to your RCA's. Ensure your amp chassis is NOT grounded to the truck with the mounting screws. Pull the ground wire for your head unit out of your wire harness and ground it directly to the firewall.

And if it is alternator noise, a good capacitor will do a nice job of filtering out A/C ripple (that is about all they are good for).

 

i turned the gain down as low as possible, and increased the voltage through the rca's and it cleared it up somewhat, im going to pull the ground for the hu out of the harness and ground it to the firewall that sounds like the best idea so far. thanks everybody

 

what spark plug are you using?

 

the factory plugs, never heard of spark plugs adding to the noise though?

 

If the ground to the firewall doesn't work, I'd try putting a 1000 MFD (1,000 micro Farad) capacitor on the alternator output terminal to ground next. It will be an electrolytic capacitor and will have a polarity (so + goes to the output and - goes to ground, I'd use the case of the alternator). I think that GM may even have a technical service bulletin on this topic.

Steve

 

i thought the same thing about the technical service, it seemed to be a big a deal awhile back. i grounded it to the firewall and that cut it out. i guess the ground in the harness wasnt good enough having to run through the factory connector