The engine in my 1985 Porsche 944 has begun cutting out intermittently. It can happen at high or low speed, but when it does it can be restarted in a few seconds and may not occur again for days. I was told initially that the ignition switch caused it, but replacing that did not fix the problem, and since then the fuel pump, filter and battery have also been replaced without effect. It's scary when this occurs at night and all lighting is lost. Hope you can help.
I haven't heard of this problem before and I would suggest it's a result of age rather than anything else. Because it's intermittent it can be hard to trace, but I would be looking for a faulty connection, perhaps one that's corroded or loose. I would take it to an independent Porsche specialist, or an auto electrician.