I have some speaker inferference on my main speakers that have an amp conectied to them. Of course it is only when the motor is running. Can an MSD box cause this?

 

Yes indeed the ingniton, espccially an after market can cause this. I had the same problem with the stock set up.

 

MSD sells a cap to eliminate this interference. I had one in my supra and works well. Good grounding and isolate the RCA from power wires will help too.

 

I have a crane ignition system but I set my system up very cleanly... no noise whatsoever. Make sure the wiring is good and clean, and the power and ground connections are adequate and clean. Also, make sure no loose wire/RCA's on the back of the deck touch any metal parts and most of all do not run the RCA's parallel to the power wire. Perpendicular if at all...

 

can be caused by a bad ground(amp) and also bad plug wires

 

Check grounds on everything. Make sure that not only the RCAs are away from the power wires, but the speaker wires are as well. If all else fails you can buy some RCA noise filters(called ground loop isolators) or somehow get a hold of some in line noise filters off of an alpine deck that go inline on your radios power leads.

John

 

I have seen this a few times, where somebody will be mounting something with a screw and screw into a speaker wire/rca, or fold a seat back and pinch a wire for metal2metal contact etc. Go through the wiring and make sure it is good.

Another thing I did was run a small length of 4 gauge from my battery terminal to the alternator and upgrade the batt. ground.