Ked928

Hi, I had just bought a 928 was cruisin down the highway for 3 hours then all of a sudden the engine stopped . I pulled to the side of the road and it just wouldn't start.

It was a hot day but wasn't overheated . Every half hour I tried to start , would try to turn but just wouldn't start. 3 hours later got a tow home cost a fortune.
Then when home it started.

Now I've been running around for about 1 month now, 1 hour drive Max and no issue.

Since then the fuel tank gauge doesn't work , not sure if related?

What should I do?
Thanks

James Bailey

Replace some relays.....quite often they heat up and shut down.

the flyin' scotsman

First, welcome to Rennlist and the world of 928 Porsche.

Would you know what maintenance was completed over the last year or 2? I'd be particularly interested in the fuel filter, pump.

The fuel pump relay can be jumpered to verify fuel pump operation.

Mrmerlin

go look at the fuel tank and see if it looks like it has imploded,
this could explain the fuel indication failure.

Has the flex plate end play check been done?
Your car can suffer this issue.

Make sure to check the position of the the drive shaft and the note how tight the rear bolt is when you remove it.
A drop of blue threadlocker and torque to 66 ft/lbs for both bolts is the protocol

James Bailey

Appears it was turning over just NOT running.....so end play is NOT the cause of stopping running especially at speed (that stalls at idle). Fuel filters almost never ever keep a car from starting they just limit the RPM as they clog. so not likely to be filter. Fuel pump is POSSIBLE problem.
Collapsed fuel tank tends to act more like a clogged fuel filter.

One possibility is the in tank strainer at the outlet on the bottom is loose and the flat plastic end got sucked up against the outlet shutting of fuel. The ride home and time would let it move away.

clearly the MOST likely on an L H Euro engine are the relays ignition, LH, fuel pump also pretty inexpensive "fix". However it could be any number of things So next time it happens (after doing the relays) it needs to be diagnosed immediately. That means having an emergency kit in the car to check things out. Just determining if it is fuel related or spark related greatly narrows the possible cause. A simple can of carb spray with a few shots down the airflow meter will immediately tell but you need the wrench to pull the air cleaner housing. If it sputters on the carb spray it is not getting fuel !!!!

Randy V

Relay, relay, relay.

How about doing an introduction thread - that's the typical way to join the forum.

jheis

Not sure if the '85 uses one, but on later cars the Crank Position Sensor can do this.

My '89 would just cut out at freeway speeds and not restart. Deteriorated connector allowed the CPS wires to ground out intermittently.

James Bailey

Yes it has a crank position sensor and needs to see that input to know it should be running.....

dzaprev

Seen a lot of CP sensor cause that exact problem.

Ked928

Thanks guys !! I really appreciate your answers and help. I'll sort this issue out now and then move onto the next. I love this forum. Cheers Ked