backitoff

Hi Guys
Car not starting or even trying to. Pulling my hair out now as I have limited electrical knowledge, and done as much as I can.
Please read the background info...............

A few weeks ago it would not start from cold. I gave the DME a wriggle and away she went......................................

The day before the most recent and final no start I was sitting in commuter traffic and the car cut out, I go straight for the DME and swap it with my spare as I was suspicious given previous problem. I noted that the relay taken out was very hot. Anyway, car drove home fine, so I figured bad DME and problem solved.
Couple of days go by and I reversed my car out of the garage, 2hrs later went to go out in the car and it would not start. Turns over, but will not, and does not attempt to fire.

OK, so it seemed that the fuel pump was not pumping as the engine was cranking. Checked out the fuel pump and established that it is OK, but is not pumping fuel when needed, so I figured that perhaps my alarm immobiliser was faulty. I got an auto electrician to come and remove my alarm in the hope that it would solve the problem. It did not.

Purchased another DME (from Porsche dealer) in case my spare had gone bad, still no joy. Had the auto electrician check connections etc and he could find no problems, but the car still will not run.

Did some more research on Rennlist (fantastic resource, you guys are legends) and all seemed to point at the flywheel sensor. Just fitted a new one, and still the same. At a complete loss now, as my knowledge and ability have been reached, and seriously thinking I may need to take it somewhere :-(

From my limited knowledge I am pretty sure there is something not sending a signal to the fuel pump / ignition to allow the car to start.

I'm about £320 in so far, and more to the point I hate things like this getting the better of me, Any suggestions would be greatly appreciated so please post em up before I go find some sharp implements to play with lol!!!!!!!!!

(BTW, battery is 2 months old and is cranking fast. Caps and rotors changed 6 months ago).

Thanks

jevvy964

The pump will prime pressure but then not fully run until the engine actually starts so you wont hear it running while its cranking. Dme relays are always warm/hot when being used so dont worry about that either. How sure are you that the flywheel sensor gap is correct? Its strange the first time it failed a new dme relay got you going but now it wont. Does your car live inside or outside?

Where are you based?

backitoff

Hi Jevvy
Not sure on how you set the gap. When I removed the mounting bracket to fit the new sensor, there did not seem to be a wy to adjust it?
Car mainly lives inside, but occasionally it has to stay out. When i bought the car 2 years ago, it had spent most of its time outside and hardly used.
I am in Essex Nr Chelmsford.

Thanks for the response

jevvy964

The gap is important and is adjusted using the slack in the holes for the 2 mounting bolts, see here:

https://rennlist.com/forums/993-foru...ce-sensor.html

backitoff

Thanks for the link, very informative. I will give it a try. Do you think the gap is so critical that it will stop a car starting up?

jevvy964

If the gap is too big it might not be picking up the rotating teeth on the flywheel which in turn will stop the pump kicking in, worth a try at least, good luck

J richard

Also reach up behind the ignition switch and make sure the plug and electrical section is firm and tight. The electrical portion of the switch is swedged on to the mechanical half. Give it a wiggle while pushing it on.on this age of car the switches are wearing out and can be the reason for a number of gremlins.

backitoff

Thanks very much guys. Will keep you posted on the progress.