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Engine Bypassing MSD ignition.

  • Thread starter Thread starter 91GTstroked
  • Start date Start date May 16, 2020

91GTstroked

15 Year Member
Jun 14, 2007
502
274
93
May 16, 2020
#1
  • May 16, 2020
  • #1
Hey guys,

So this is the second time I've attempted this. Once bypassed, the car seems to run the same (at idle at least) as if the msd is hooked up.

My problem is my aftermarket Autometer tach is erratic while idling. It's bouncing from 1,000-2000 rpms even though the engine isn't.

I took the tach trigger wire from the MSD and attached it to the negative side of the ignition coil.

What I can't understand is why I have another wire spliced into the positive side of the ignition coil. Per all the instructions I've found on installing a MSD ignition, no wire should need to go to it.

Both of these wires that I mentioned I believe go inside the car. I have a Florida 5.0 Autometer gauge setup.

My MSD is mounted right where the battery normally is. I planned on putting the battery back in the engine bay. So I thought about going back to the stock ignition setup. If I can't figure this out, I may just try to mount the MSD ignition box inside the fender.

Sorry for the long post.
 

91GTstroked

15 Year Member
Jun 14, 2007
502
274
93
May 17, 2020
#2
  • May 17, 2020
  • #2
Wired it back to the way it originally was. It's all fine again, I'll leave it alone.
 
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