puma1824

Well looks like my engine stalling is getting worse. I just purchased the car (1991 964 C4) almost two weeks ago and stalled the car a couple times. At first I thought it was because I wasn't used to the clutch BUT today it was definitely not me.

Here's the situation when it occured today.

- 94 Degrees, Sunny, some humidity.
- Filled tank with 93 Octane (Exxon)
- Began a 30 mile trip
- When I was near my destination (29 miles) at the end of an exit ramp was a stop light.
- Stopped at the end of the light. Engine stalled! No power, all warning lights on.

Other occurences before today:
- Raining and around 85 degrees
- 1/4 tank full - first start (engine cold)
- drive around block stalled going into parking lot. Again no power all warning lights.

======

- Sunny day, ~89 degrees
- 10 mile trip
- Stalled pulling into parking lot.

Please help...I don't want to stall in a bad situation such as in traffic or while truning on an exit ramp.

Thanks,
Puma

jimq

DME?
Is it a light weight flywheel?
Are you under power and it cuts off or when you slow to stop?
Maybe idle is to slow?

DarrylH

If the car stalls when clutch goes in and accelerator lifts, it could be the idle system - stabiliser, air flow meter, idle microswitch...there's some good information if you search on "ISV" - it's a place to start.

puma1824

DME is on the way from Sunset Imports. (I thought DME only effected starting? - could be wrong) So I'll try that when it gets here. As for the light weight flywheel...I have and the previous owner has no idea. I'm generally slowing down to stop NOT under power. What speed should the car be idling?

I'll start observing more and researching "ISV"

Thanks,
Puma

Marc Shaw

DME is the engine's "brains" and controls air/fuel mixture at all rpm's plus a host of other things - not just starting.

Idle speed is approx. 800 rmp, IIRC.

Marc

puma1824

Oops I meant DME relay on the way the DME relay just for starting. Do you think I need to replace the whole DME?

jimq

The DME is controled by the relay. The relay does other things I think also to the DME. Do just the relay!

Gary R.

Doubtful, you could try a DME reset though. Do a search, I think I found the procedure on the DIY forum..

jimc67

I have a similar problem with my 92 964, and have limited it to the first twenty minutes or so of driving. It happens only when the air conditioning is on. It does not stall when the AC is off. Stalls when clutch is in and braking for a stop.

Marc Shaw

Goodness, no!

Replace just the relay and carry a spare (relay, not DME )

Marc

C4porsche964

I have a 92 C4 and this has happened to me a few times. Other friends with 964's have also mentioned it. It happens when the clutch is in and you rev the engine and then let off on the accelerator. The rpm's drop a little too much and don't recover and the engine stalls. The good news is that it starts right back up. I cleaned my air filter and haven't had the problem since. Obviously there are many things that could contribute, but the air filter is a simple thing to check.

bhensarl

I had the same problem last week (while my fiancee was in town ). About 2 times out of 10 if I was less than super smooth while putting the clutch in coming to a stop the car would stall. I'd never had the problem before, and I never had any trouble starting the car up again. After refilling the tank I haven't had anything close to a relapse. I hope your fix is as simple as mine was.
Brian

964_C2

At some point you should really try and find out of the car has a light flywheel (for your own sanity). I have one in my car and with the AC on its damn right dangerous to drive in traffic. It will stall probably 30% of every time I stop the car, no matter how gentle or careful I am. If you have a LFW, it will rule out many things to look at.

Rennen

When you open the hood with the car running, are you able to hear any discharge from the ignition system? If you happen to have bad, leaking ignition wires, you will be able to hear and sometimes see leaking of spark around the distributors or coils. It's a rhythmic "pop-pop-pop". I have been having a problem like yours and I'm convinced it is caused by leaking ignition.

robbed666

I had a simlar problem a few weeks ago. Did a 50 mile trip, no problems, parked up. Returned to the car 3 hours later. Started up and drove down the street , coming to a stop a the T/lights , cut out. did at virtually every stop in town stop. Got home, still cutting out when off the gas. Next day repaired (poor soldered joints) then, changed DME relay. Drove to work (4 mile) still doing it, even from cold. Started the car to come home, cloud of white smoke. That cleared within a second or two. been absolutely fine since ( 500 miles + all types of driving) !? inlet oil contamination ? I don't know.