What Happened??

[Karl_W911]

Yesterday afternoon, I went to break for a red light and as I did, the car lost all power, stalled or died on the spot. Felt the car rumble a bit, then die.

I tried swapping in my spare DME relay(I already put in a new one earlier yesterday) and that did nothing. It's soldered so the fuel pump runs indefinitely, so plugging that one in, I could hear the fuel pump whirring so I don't think it's that.

I have yet to check for spark. The car cranks, but doesn't fire up at all. What worries me most is the fact that I made an appointment to have my belts retentioned Friday, as I have about 3000 miles since I put my new belts in. I'm praying it's something like sensors or a coil failure and not the worst case scenario.

Any ideas as to what I should look for? Symptoms of a belt that's skipped a tooth or slipped? Am I just jumping to worst conclusions?

[v2rocket_aka944]

ignition switch.

[grendiers]

Also, check the rotor, to see if the little rotor set-screw is missing. Engine dies a sudden death when it happens of course. Happened to me, took four days to figure it out, after doing everything else for naught~! Had to change the oil afterwards from cranking.

[FrenchToast]

I would check the reference sensor plug. It's at the back of the engine, on the top.

[Skytrooper]

Originally Posted by frenchtoast

i would check the reference sensor plug. It's at the back of the engine, on the top.

+1

[Karl_W911]

Originally Posted by v2rocket_aka944

ignition switch.

Impossible, I just put a new one in last Monday when I broke down at a concours event the day before.

Originally Posted by grendiers

Also, check the rotor, to see if the little rotor set-screw is missing. Engine dies a sudden death when it happens of course. Happened to me, took four days to figure it out, after doing everything else for naught~! Had to change the oil afterwards from cranking.

I'll take a look after work. Is it a special scree that needs ordering or anything, if it's missing?

Originally Posted by FrenchToast

I would check the reference sensor plug. It's at the back of the engine, on the top.

I'll do that as well after work.

[Mr. Squid]

It doesn't sound like a belt issue, if your belt snapped it would sound quite a bit different when cranking over.

Reference sensors/connectors would be a good place to start. The coil on these cars rarely cause any issues. You may also have a DME issue...do you have any other Porsche 944 guys near you that you could swap DME's with just to test?

Years ago I had a similar issue with my car, I was backing out of a driveway, stopped to check for oncoming traffic. The car died, it would crank fine but not start, after checking the same things that you have checked I called the local junkyard (they used to specialize in European cars) and picked up a DME. Few minutes later I had a running car.

You may want to check clarks-garage for testing the reference sensors.

[Karl_W911]

I'm not so worried that the belt snapped; rather, that it skipped some teeth or had enough slack to cause some havoc.

I'll check these sensors and connectors to the best of my ability, but oh god, I'll not be happy if the DME box has failed. How can I check that?

[Karl_W911]

Update:

1. The sensors are plugged in firmly in place, not loose at all.

2. The set screw is still in place.

[rick13]

Does the tach bounce?

[PDX-944]

check the timing belt.

I came to a stop, car stalled gently. cranked over just fine, just whined a little more with bad compression. stripped a bunch of TB teeth off. I was 1000 miles from replacing it again. but oil had leaked on it.

also, sometimes mine will crank and crank but not start until you gently kick the fuse box. lol
I need to clean up some of the connections, I just haven't yet. but usually a shake of the wires going in the back of the fuse box gets me going in a second or two.
same with my headlights not working.

[Karl_W911]

Originally Posted by PDX-944

check the timing belt.

I came to a stop, car stalled gently. cranked over just fine, just whined a little more with bad compression. stripped a bunch of TB teeth off. I was 1000 miles from replacing it again. but oil had leaked on it.

also, sometimes mine will crank and crank but not start until you gently kick the fuse box. lol
I need to clean up some of the connections, I just haven't yet. but usually a shake of the wires going in the back of the fuse box gets me going in a second or two.
same with my headlights not working.

That's somewhat how I'd describe what happened to me. Came to a stop, and the engine cut out/off. What should I check on the timing belt, if it's actually gone wrong?

I'll gently kick the fuse box as well, for giggles in this disappointing situation.

[Karl_W911]

Originally Posted by rick13

Does the tach bounce?

The tach doesn't bounce at all. What does that mean??

[PDX-944]

Originally Posted by Karl_W911

The tach doesn't bounce at all. What does that mean??

speed or reference sensor is suspect
check the plugs, ive had several break. theyre the two at the back of the intake manifold, look identical

[jpk]

The tach gets it's signal from the engine speed sensor (through the DME). If you get no tach bounce, either the DME is bad or it doesn't see the signal from the engine speed sensor.

One culprit could be the connectors for the sensors. They crumbled on my early car.

[Karl_W911]

I tried pulling the connectors off, and they wouldn't budge. Gonna have to go with a vice clamp later to force them off.

Can they cleaned like contacts and points and such? Just with some elbow grease and sandpaper?

Also, is there any way I can quickly test to see which of those two things is the culprit?

[PDX-944]

Originally Posted by Karl_W911

I tried pulling the connectors off, and they wouldn't budge. Gonna have to go with a vice clamp later to force them off.

Can they cleaned like contacts and points and such? Just with some elbow grease and sandpaper?

Also, is there any way I can quickly test to see which of those two things is the culprit?

don't use vice grips. they'll break. ive broken several by hand. theres a metal clip on the plugs, its shaped like a C. you must get the clip off by spreading the ends. then they will unplug and come off the bracket holding them in place

[Karl_W911]

Originally Posted by PDX-944

don't use vice grips. they'll break. ive broken several by hand. theres a metal clip on the plugs, its shaped like a C. you must get the clip off by spreading the ends. then they will unplug and come off the bracket holding them in place

Oh! That's what those things are. Thanks for the heads up, good thing I'm not home to vent my frustration with a vice grip..

[PDX-944]

yep, they can be a pain! you need a small hook or tiny screwdriver to slide the ends of the clip. a pick tool is best

[Karl_W911]

Thank god I just bought a really small and thin screw driver for another occasion!