Engine noise after satellite radio

I had this customer come in yesterday and wanted a sat. radio installed.  It was a sporster.  So he wanted the power hard wired into the vehicle.  The car was  a Chevy S10 p/up truck.  He had a 4 chnl amp in there for about 6 years.  Anyway, to hard wire the sat radio, I tagged the acc. and ground from behind his deck.  Put everything back together, sat radio works fine, turn the car on and there was engine noise.  I regrounded the radio and there was still noise.  I added a ground loop isolator for a temp. fix, but you can still hear the engine noise.  Not as bad, but still there.  I didn't unplug any rca's.  The only thing that I touched was the ground and acc.  Can anyone tell me the problem?  Thanks

Anyone??

Nope.  The noise is there when its on radio, sat radio or cd.

What happens if you completely remove the sat. Your positive the noise wasn't there before.

I removed the sat and the noise is still there.  I'm positive the noise wasn't there cause I did a check list on the car before it came in, cranked the music up cause I wanted to hear how it sounded.  I noticed the power wire and the cables were all ran on the same side.  I didn't want to rerun it cause the noise wasn't there when it came in. 

Well I'm almost positive it's a grounding issue.  Did you try grounding the rca shields?  You can also link the deck ground to the amp ground.  Make sure they're all clean and tight.My ex once told me I have a perfect face for radio.

Check the routing or the RCA cables, and make sure they are not pinched, smashed, torn, or near any positive wires.