Do Caps cause engine noise?

My system went nuts last night, the subs started pounding uncontrolably and a high pitched engine noise started in all the speakers. I thought I might have blown another amp, but I took the sub amp out and I still have the engine noise.  Everything was working great with no problems and I had been driving about 20 minutes or so, and then all of a sudden it all went nuts, I wasn't even listening to it loud about level 9 or so.   I have a Pioneer DEH-80mp head unit, 4 Pioneer 4 ways in the doors and rear roof, 6 11/2" tweeters, a Vibe 600 watt 4 channel amp, 2 kicker 15" L7's, a Mark Anthony 3000D mono-block, 3 8" boss monitors, a slim PS2, conected to the head unit by a CB-10(aux. input by Pioneer) and a Boss signal booster for the monitors.  and a 100 farad cap by Lanzar, model # Opticap1000.  I don't  know if it matters but I have 0 gauge running from the batt. to the cap. and 4 gauge from the cap to the 2 amps. and the amps and cap are grounded to the bolts that bolt down the back seats. Please help I can't stand having the noise and not having my bump.

Do you have a good ground connection? As in did you scrape away all paint until you have bare metal then ground the amps to the bare metal?

Sounds very similar to an install I did in a boat about a year ago.  The guys system was making a crazy screaming noise so we switched out everything in his system until we finally figured out that there was something was wrong with the cap and feeding back on everything else.  It drove us nuts!

Ok I don't think its the cap, I took it out and still had the engine noise.  But as I was removing speaker leads from the 4 channelm the front 2 channels where fine, came off with no problems, but as soon as I touched the rear channel with the screw driver I got this loud cop siren sound from the speakers.  Also with one wire to that channel still hooked up when I touched the wire that was off with my finger I got a strange noise through the same speaker.  When I touched the other rear channel with the screw driver the noise went away for a split second but came back.  So wouldn't that mean the 4 channel is bad?