Impaler

A couple times this happened when downshifting/braking before a stoplight. Recently it happend once when clutching/upshifting and in mid drive clutching/downshifting.
I took it to two dealers and one Indy, no one can reproduce the problem or has any ideas.
Anyone on this forum ever had the same experience? If so, what did you do?

bonus12

Hmmm I have had experiences with the (-) battery terminal/cable being rusted/loose. It caused some very strange symptoms when I would brake hard, turn hard, or accelerate. Basically, the battery would shift around in the comparment and alter the connections of the components of the neg. terminal.

Yes, the car died mid-drive, and sometimes I could rectify the peril mid-flight by slamming the accelerator at boost, which would shove the battery back and restablish connection. Then I could start her up.

This, in addition to a bad battery and a battery drain, was very confusing! The above problem also caused non-start problems, analogous to a bad dme relay. At the time, my dme relay was also going bad, to really complicate things. Ooh, rough times. I almost forgot about those.

Good luck with yours. It sounds electrical regardless.

bobzdar

Check the connections on the underside of the fuse box and make sure they're seated properly. You could be hitting the wire harness when you press the clutch and wiggling the connection enough for it to kill the engine.

kev951

check your speed and referrence sensors please. look at the connectors, remove the sensors and look for debris stuck to them.

jhowell371

+1 on the reference sensors. Just went thru this on my brother's 944.

NoRush993/951

Check the connectors at the back middle of the engine compartment along the firewall that conducts the spark. That connector is plastic and over time doesn't stay snapped tight together. The engine just dies when the spark is cut off. I can't remember the name of this wire, but my mechanic welded them together as an inexpensive fix instead of replacing the wiring.

gregeast

Sound similar to issues I had with cracked solder joints in my DME

Symptoms:
- Car would die suddenly and intermittently
- Shaking the DME would get it running again (even going down the road a couple of times!)
- Frequency of problem was increasing

After a fair bit of searching on the list I surmised that it must be a cracked solder joint in the DME. I found several threads but no pictures.

Based on what I read, the failure was typically on the leads from 'the big silver transistor'. Here's what that looks like:


There are three leads that come off this transistor and here is what they looked like on the bottom of the board. Notice the tiny cracks on the two outside posts?


Out with the trusty soldering iron, melt the solder joints and then let it 'freeze' and life is good. Only time will tell of course if this really was the fix but it had died several times on me earlier today and so far this evening it's running like a champ.

The hardest part was soldering with my fingers crossed

Impaler

Where are the speed and reference sensors located?

Chunkerz

On top of the bellhousing between the engine and the firewall.

FrenchToast

+1 on Reference sensor, DME relay, DME connection, DME, wire looms under fusebox, etc.

Also, DO NOT remove the key while moving!

Impaler

Called the shops, the techs did all the above, no joy, any other recommendations?

gregeast

Did they really crack open the DME and resolder those joints?

Spokayman

I had a similar problem on a 944S2. The engine would just die while cruising in gear (any gear). It was as if someone had turned the ignition switch off.
It would always immediately restart, and I could not replicate the problem for a mechanic because it only happened 3-4 times over a period of two years.
I sold the car before I fixed the problem so never found the source, but I always suspected the ignition switch or one of the ignition wires.

Zeff

+1 on dme. Also does your car have an alarm box? Check that too. If the alarm is bypassed and those wires go bad it can cause similar issues. I just went through this on Sunday. I had a couple shut offs earlier in the week and had an electrical friend look at things. Definitely my dme. I need to message Rogue and see what he says. I had lots of corrosion just on the dme. Everything else in the kick panel was fine ( tuner, logger, klr etc) i still had my old dme and the car ran with zero issues.

Mister Quickie

I doubt they resoldered the DME joints, I'll inquire about an alarm box bypass