Coil trouble?

[Ole Petter]

I had some faulty/burnt earth-wires to the coil in my 1975 911S. I had them exchanged and the engine ran better. But when the engine is warm there is some studder/hesitation at highter rpm's. Today the engine died. I got it started after some time, but then it died just a kilometer down the road.

There is a Permatune CD-box and Coil in the car. I can't find a Permatune Coil at the Pelican Pars anymore, is there another coil that I could use?

[HarryD]

I have heard a MSD Hi Vibration coil would work.

It may be your Permatune overheating. Try this, the next time it dies, see if it is hot. If so, place a few ice cubes on it and see if it suddenly works. If so, your Permatune is on the way out and should be replaced.

[The cap'n]

First, what caused the ground wires to fail? THAT would be my first thing to look at. The loss of spark when warm/hot is a common Permatune failure, despite what their help line says. I've seen this failure with new-out-of-the-box units. Personally, I'd find a Bosch core unit and have it reconditioned by one of the folks here who do that (Loren or Ingo). Then you can use a Bosch Blue coil.

The Cap'n

[Uncle Enzo]

I had the exact same issue but sadly, I cant offer you any advice. I am running a stock coil and CDI. What sucks is I cant get it to do it again. After limping it home, I tried like mad to get it to poop out again and could not. I did find my points were shot but that about it. I would go with a new coil first then if that does not resolve the issue take a look at the permatune.

[Ole Petter]

Many thanks for Your replies and help! The Permatune unit was not warm or hot when the car died. I will try to fit a MSD coil as You recommend first, if this doesn't help then the Permatune CD unit will be replaced, I guess with a MSD unit...

Again many thanks