Engine Noise

I got a good problem that hopefully somebody can help me out with.  I have a 1985 mustang, trying to run a decent system, spent about 4 years cleaning it up, taking all the rats nest of factory wiring that came with the car, finally starting building a system in it, and bam, engine noise.   Three systems ago I put a noise filter which does ignition, 12V and ground, and that got rid of my problem, back then that is.  Then I decided to switch head units, add two amps and good insulated RCA's, ran away from any power wires, proper 4 gauge wires with good solid grounds, upgraded the battery, new alternator, voltage regulator(regular maintenance on old cars) and factory ground and power wires from the terminals.  I have two sets of speakers in dash and door, none in rear, 2 12 inch subs, tantrum amp, alpine 4 channel, pioneer 1/2 din 8 band equalizer, pioneer head unit(DEH7500) 1/2 farad stiffening cap, JL 12 inch w 0's, and I still get the engine noise!  all power is routed to the back, same with ground all to one point, tried this to see if it would eliminate noise problems, it didn't.  Any input would be appreciated.Kyle@Audio Obsession Sound

I was going to guess that you might have a Pioneer head unit, is it grounded to where the amps are?Top Secret, I can tell you but then my wife will kill me.

For both forbidden and ravendarat, yes the deck was run to the same ground point as the amp, but either grounding it to a bare metal ground point near the deck in three different places or running it back didn't make a difference, and the ground point for the crossover underneath the deck is grounded seperate from the deck.Kyle@Audio Obsession Sound

Bypass (or remove) the EQ and see if your problem goes away.

I did that too, went away alittle bit, but noise is still there.Kyle@Audio Obsession Sound

Engine ground strap replaced and upgraded through and through, and I don't think that the alternator or the regulator are the source because I had the noise even before I replaced them. I know this problem is probably minor to fix, its just pinpointing the source thats taking so long.  Its not really loud noise, I just hate noise.  Kyle@Audio Obsession Sound

Sometimes it is a very simple thing like a stray strand on a speaker wire touching ground somewhere... but these are always the hardest problems to find.  Good luck!