Hello all, I've got a 350SBC 95 year model with swirl port heads...anyway, the other day I was cleaning my truck out and I had my system on (sub,amp,cap) with only the accessory on. After some time I figured I better check to make sure my truck would still crank. After starting the engine and making sure all was ok I shut it off and proceeded again to only have the music on. After some time again my truck would not start ok I figured my battery was dead so after jumping it my truck started only this time it was weird. Normally, my truck rumbles and idles around 6-700RPM (headers,dual flow masters) but now, it doesn't want to start on its own during cold starts. I have to pump the gas pedal to get it to start and when it does start, it idles at 500RPM and once it warms up it goes up to 600RPM. After that, it'll start fine just no rumble, it's quiet, almost like a new car. Anyway, to make matters worse, there is a strange rattling sound coming from the bottom end of the motor that happens at random times (stopping, after revving engine, holding gas pedal at about 1000RPM range) I've checked the plugs and changed the wires, advanced the distributor about 2degrees, ran fuel system cleaner, checked all vacuum lines, changed fuel pump, changed fuel filter, checked injectors, checked battery, starter, and alternator...all of these are fine. I also noticed a great but of condensation at the end of the tailpipe even after the engine was warmed up and having run the engine a good bit. It doesn't stall while normal driving, no hesitation, great launches, but if I tap the pedal and let it go quickly in Drive or Reverse, it'll stall.
Any other ideas?