When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
@Macovp I just had very similar thing happen to my 993, while driving on Highway 9 toward Boulder Creek. I just filled up the gas tank at the beginning of the drive. Engine cut out while on 2nd gear at about 4500RPM. Attempt to restart the car first failed, with Engine Fan belt light on dash. Trying again after 5 minutes worked fine and cleared the dash.
Don Wise's shop replaced my fan and alternator belts about 2 months ago. On the phone this afternoon, he suggested it might be the alternator. I also found out that my voltage regular is probably bad, with 15.8v when off and 16.6v when idling. Will bring the car in to Don next Wednesday.
Did your issue come back after the DME relay replacement?
Sudden "engine cut out" wouldn't normally be an alternator thing. Take the extreme case where the belt breaks - the car would run on battery until it got too low, at which point the dash would light up like a Christmas tree. It may take many miles and the car would eventually stall, but it wouldn't happen suddenly. The fact that the car cranked and started only a few minutes after the stoppage says that the battery had plenty of juice left, so alternator was probably working. The voltage regulator should definitely be looked into but it sounds unrelated.
Sudden "engine cut out" wouldn't normally be an alternator thing. Take the extreme case where the belt breaks - the car would run on battery until it got too low, at which point the dash would light up like a Christmas tree. It may take many miles and the car would eventually stall, but it wouldn't happen suddenly. The fact that the car cranked and started only a few minutes after the stoppage says that the battery had plenty of juice left, so alternator was probably working. The voltage regulator should definitely be looked into but it sounds unrelated.
Makes sense. I'll definitely replace the voltage regulator but it might not have led to the power loss in a direct way.
I'll go ahead with the DME relay/fuel filter/negative power cable replacements to see if the problem goes away.
Sudden "engine cut out" wouldn't normally be an alternator thing. Take the extreme case where the belt breaks - the car would run on battery until it got too low, at which point the dash would light up like a Christmas tree. It may take many miles and the car would eventually stall, but it wouldn't happen suddenly. The fact that the car cranked and started only a few minutes after the stoppage says that the battery had plenty of juice left, so alternator was probably working. The voltage regulator should definitely be looked into but it sounds unrelated.
not sure I agree. 16V could start voltage clamps conducting etc. in the same way that a high impedance ground wire can mess with the sensitive ECU so can over voltage effects.
Regardless, I wouldn’t drive a car with 16V out the alternator. That must be fixed.
I had a similar problem and replaced the DME relay and the battery ground cable per several threads on this topic. While I have not had issues in the last 6 months, reading this thread makes me re-think my scenario. My engine cut-out or stalling generally has been after I've been in stop and go traffic, or parked and waiting for someone with the car idling. Generally, it's hot weather and the AC has been running. My C2S does have an RS pulley set-up, so could this, combined with my scenario's, contribute to my stalling? In the parked scenario, idling with the AC on, it would stall when backing out of the parking spot. The dash would all light up, then it might take a couple of attempts to restart, but always has turned over.
not sure I agree. 16V could start voltage clamps conducting etc. in the same way that a high impedance ground wire can mess with the sensitive ECU so can over voltage effects.
Regardless, I wouldn’t drive a car with 16V out the alternator. That must be fixed.
Yes, that's asking for trouble!
__________________
Loren
Systems Consulting - Automotive Electronics
Specializing in Porsche cars http://www.systemsc.com/
I had a similar problem and replaced the DME relay and the battery ground cable per several threads on this topic. While I have not had issues in the last 6 months, reading this thread makes me re-think my scenario. My engine cut-out or stalling generally has been after I've been in stop and go traffic, or parked and waiting for someone with the car idling. Generally, it's hot weather and the AC has been running. My C2S does have an RS pulley set-up, so could this, combined with my scenario's, contribute to my stalling? In the parked scenario, idling with the AC on, it would stall when backing out of the parking spot. The dash would all light up, then it might take a couple of attempts to restart, but always has turned over.
I had some issues with a previous 997 where the starter harness wiring would get hot and lose conductivity. So after filling up gas, it'd struggle to crank and I'd have to wait 10 minutes for it to cool. It sounded like these were symptoms up until you mentioned that it cuts out when the motor is running. It might be pulley related with regard to how much load is being asked of the engine idle.
I had some issues with a previous 997 where the starter harness wiring would get hot and lose conductivity. So after filling up gas, it'd struggle to crank and I'd have to wait 10 minutes for it to cool. It sounded like these were symptoms up until you mentioned that it cuts out when the motor is running. It might be pulley related with regard to how much load is being asked of the engine idle.
There was a Porsche recall on the 997 starter to alt wire.
04-15-2023, 12:48 AM
