Main Menu

Engine Stalls

Electrical and Electronic

Model: 993 C4S, Year:1996, Mileage:70,000, Type of use:Both Street & Track
Joel,This is a follow up to a Q7A previously published (repeated below)I have a very similar problem to the one described below. However, after stalling the engine will crank, but not start right away. After 3 or 4 minutes the car starts. The first time this happened was on the track at the end of a long front straight. The next time was on the way home from the track at 6th gear 75 MPH cruise. I have replaced both the DME relay and the fuel pump (it had been getting nosier). Car ran well for 2 days and then it stalled again at 45 MPH. Cranked but did not start for a few minutes. Then everything worked and seemed normal.FYI, I installed a TPC supercharger along with a complete engine rebuild 3 years ago and the car has been bulletproof and very competitive in NASA Time Trial competition. Because the supercharger has been added the local Porsche dealer does not want to touch the car. Any suggestions? Earlier you provided the following Q&A:1995 993 Stalling Diagnosis Needed996, 993 | Electrical and ElectronicVehicle Information: Model: 1995 993; Year: 1995; Body Type: Coupe; Total Mileage: 65000; Four times now my car has died while driving with no warning. The car is a 95 993, with about 65000 miles. The DME relay has been replaced, as has the wiring harness. First time, about five miles from home and travelling about 40mph it dies, just like the key was turned off. Running fine, then dead. All of the dash warning lights were on, so I pulled over, popped the engine lid and looked in, expecting to see the alternator belt broken. Not so. I tried to restart it, and it fired right up. Next, as I pull into my parking garage, it does the same thing. No warning, running fine, then dead. Fired right back up when I turn the key. Third time, as I pull into my subdivision, dies the same way. Fourth time, dies the same way as I pull into my parking garage at work. My first thought was the DME relay, but I replaced the 944-part numbered relay with the updated part number years ago. Second thought was the wiring harness, but that was replaced under the recall several years ago. Third thought, alternator, but why would the failure be periodic? On the second, third and forth times, I think depressing the clutch as I was coming to a stop. What say you? Thanks in advance. Car Prep: Modified Car Use: Combination Street and Track Total Mileage: 65000 Don Magee [HCT]5/21/2008 8:35:33 AMYou changed the DME relay "years ago"? I would try a fresh one first, as it could be failing you intermittently, regardless of part number. After that I would plug in the computer with the Durametric software and check for any fault codes. Then if we still have nothing to go on, I would think about changing the crank position sensor. When it stalls, does it always restart? After it stalls, can you still hear the fuel pump humming? It could be other things as well, it could even need a new ECU. But I think we need a little more information to come to any conclusions. Joel Reiser - PCA WebSite - 5/21/2008

You must log in to view answers associated with technical questions. Join PCA to participate in our community.
No votes yet