I've had engine noise through my front speakers for the longest time now. I kind find were its coming from. I've run just about ever test I could think of to trace it and came up with nothing.

Then I remembered that someone once told me they sold their MSD ignition box because it was giving them so much engine noise in their speakers.

Anyone else ever had this? Do you think thats were my problem lays?

Thanks!

-Ken

 

Possibly. I tried one of those Omni Magnum ignitions in my Tahoe and it made a lot of noise in my stereo system. It might also be bad spark plug cables that aren't shielded adequately.

 

I have heard that as well....

 

OK... I disconnected the MSD from the coil and plugged the original wiring in. Unpluged the power but left it grounded.

The noise went away drastically but I still had some feed going through. Leaving the unit grounded wouldn't have done that would it?

What else could it be?

 

If theres no power going to the MSD then it can't be the problem. What about your plug wires? Are they factory or were they part of the MSD ignition?

 

There GM Performance wires. I believe there 7.5 or 8mm wires.

Mind you they are about three or four years old. You think the'd be going bad already?

Would MSD wires be better sheilded or worse?

 

I guess its like a combo deal... MSD box + bad wires = engine noise!

What can I do to get rid of it? Is there other ignition boxes that don't produce as much interferiance?

 

Personally I would can the MSD alltogether. Thats what I did with the Omni Magnum I had for my Tahoe. I didn't notice ANY improvements that they claimed their ignition would provide.

I would definitely replace the old plug wires though.

 

What exactly causeds the engine noise?
Is it radiation (for lack of a better word) from the wires?
Is it a ground issue? If so would a ground loop isolater on the MSD help?

Would you say a good aftermarket distributer, coil, and wires will keep up the spark just as well as an MSD ignition box? Or anyother brand for that matter.

 

The noise is caused by what is called RFI (radio frequency interference) that is radiated by the ignition and is picked up by the stereo. Just how it enters the stereo needs to be found. It could be the antenna. To test for this you need what is called a dummy load. This consists of a plug that goes into the antenna jack of the HU. It has a 75 ohm resistor in it that takes the place of the antenna. If this removes the noise then you know that the noise is entering thru the antenna. You can try an antenna noise filter or possibly rerouting or even replacing the antenna cable. The noise can also be picked up by the RCA cables. This is why you need to use RCA cables that use "twisted pair" construction. This type of cable has much better noise rejection qualities than shielded RCA's which are totally useless in a car stereo installation.

As for the after-market ignition... I think they are all junk and hype.