986 Engine cuts out

[kk2002s]

I am on the testing phase of my solution to:
Car would start and run fine. Then after several miles stall and couldn't re-fire. Wait 10 - 15 mins and could restart and drive fine. This would repeat.
I started with fuel pump relay.
- Got car running until stall. Could feel Relay was very hot.
- Pulled relay and put in jumper (plugs 30 & 87 I believe)
- I could immediately hear the Fuel pump start running.
- I then started car with jumper and it ran fine.
- Pulled jumper with car running and the car slowly stalled. Same behavior I experienced while driving. Because the Fuel pump was no longer running.
- Placed hot Relay back in and car would not fire
- Cooled down relay with cold air, plugged back in and car fired right up

So now with new relay I'm driving around with fuse covers off and I touch the relay after I stop to see if it gets exceptionally hot. This would indicate to me something else is causing relay to fail.
So far so good but I've only driven 40-50 miles over a few days.
The relay does get pretty warm but not to hot to keep finger against as before
Hope this gives you some ideas

[Alan2b]

Hi. A new member here.
I seem to have a very similar problem.
Engine suddenly cuts out with no warning and no CEL or error codes.
Took it to Porsche and they said it was cats had failed due to ignition coil packs which were failing and causing missfires (burning out cats due to unburnt fuel getting into them).
Changed coil packs, cats & lambda sensors & thought problem had gone (200miles + driven without problem) but happened again at weekend.
Initially after it dies, it will just crank over and refuse to fire.
After waiting a bit longer (about 10mins) it fires and goes into fast idle - but after a few seconds revs start to drop (to normal idle) and at this point it pops & bangs and cuts out. At this point giving it a bit of boot you can keep it going for a bit, but just more backfires etc and eventually dies.
I had been thinking it could have been heat related but last time it happened almost immediately (the car being started from almost cold - having been stopped just a couple of hours before - after 60miles without problem).
Dodgy relay sound a possibilty - burnt contacts??
Did you get to the bottom of the fault & which relay was getting hot?
Any help / suggestions would be appreciated.

[BYprodriver]

[QUOTE=Alan2b;580189]Hi. A new member here.
I seem to have a very similar problem.
Engine suddenly cuts out with no warning and no CEL or error codes.
Took it to Porsche and they said it was cats had failed due to ignition coil packs which were failing and causing missfires (burning out cats due to unburnt fuel getting into them).
Changed coil packs, cats & lambda sensors & thought problem had gone (200miles + driven without problem) but happened again at weekend.
Initially after it dies, it will just crank over and refuse to fire.
After waiting a bit longer (about 10mins) it fires and goes into fast idle - but after a few seconds revs start to drop (to normal idle) and at this point it pops & bangs and cuts out. At this point giving it a bit of boot you can keep it going for a bit, but just more backfires etc and eventually dies.
I had been thinking it could have been heat related but last time it happened almost immediately (the car being started from almost cold - having been stopped just a couple of hours before - after 60miles without problem).
Dodgy relay sound a possibilty - burnt contacts??
Did you get to the bottom of the fault & which relay was getting hot?
Any help / suggestions would be appreciated.[/QUOTE


Thank you & every other poster here that searched instead of starting a new thread. It really makes the forum better rather than more cluttered.

I don't see how converter condition can prevent a 986 from starting. Lots of fuel pumps failing these days especially when the tank is low on fuel which is the only thing that cools the pump.

My 2000 S has it's original crank position sensor.