My 930 is Cutting Out...

[FlashGordon]

After I am underway for 10 minutes or so, the car will hesitate and sputter. Seems like lack of fuel or spark. Then corrects itself for a bit and then the same intermittent problem. Eventually, it cuts out entirely and stalls. Car will not start for 10-15 mins or so (will not turn over). It will then start again, but will cut out (stall) again and each successive time this occurs it seems to take longer and longer before it will re-start.

I'm bummed. I had a ton of work done to it this past winter and have only gotten to drive the car about five hundred miles since. I had this same problem a few months back. The shop replaced ignition coil and put in a new Permatune CD box. This seemed to correct the problem for a few hundred miles, but now it's back. Car was towed back to the shop last night.

I'm looking for some suggestions on where to look next -or- perhaps someone who has gone down this road with the same problems/symptoms before?

Finally, does anyone think I'm out of line with my thought that the shop should do this on their dime (since it was potentially misdiagnosed with the CD box and coil?) I consider myself a very fair person and if my thinking is flawed I have no problem paying what is fair.

My car is an '87 930. K-27 7200, H/E/I, larger IC, 1 bar.

Thanks guys.

[356-930]

Originally Posted by FlashGordon

After I am underway for 10 minutes or so, the car will hesitate and sputter. Seems like lack of fuel or spark. Then corrects itself for a bit and then the same intermittent problem. Eventually, it cuts out entirely and stalls. Car will not start for 10-15 mins or so (will not turn over). . . .

If it quits and wont even turn over, you're probably loosing +12v to the ignition switch. When the switch fed and distributed +12v is lost the CDI has no power so it dies. No power to trip the starter solenoid when you try to re-start so it won't pull in. A key symptom of failure is "will not turn over." Not a fuel related issue.

[NathanUK]

Check your earth leads including the one from the chassis to the tranny.

[DDDD]

Without starting a flame session, I have heard that Permatunes have hot weather running issues and somebody on this forum replaced his Permatune with a MSD to solve this problem. My mechanic says he replaced about three permatunes in the same vehicle once and now he doesn't use them.

I am not trying to send you on a wild goose chase, but it is something to at least consider that the permatune went bad, if you don't find anything else.

As far as the shop fixing it on their dime, good luck. I have not met a Porsche shop locally that will fix any mistake on their dime. Maybe your shop is better...