Postby SR » October 15th, 2004, 9:00 am
make sure the rca wires ae separate from the power wires and the mian harness wires for the car
ensure all equipment are properly grounded and typically with multiple amplifiers
grounded to the same pt and the ground is secure and clean
replace / upgrade the ground wire from the battery to the chassis of the vehicle
these are basic checks you need to do
now if the vehicle has racing plug wires and racing plugs you may not be able to get rid of all the engine noise