964 911-C2 engine stalls due to low mass flywheel
 

I have a 1992 964 911-C2, 3.6L with a lightweight clutch and low-mass flywheel. Whenever I am driving with the A/C operating, if I disengage the clutch and simply let the engine speed drop on its own, the car will often (50% of the time) stall. It would appear that with the reduced mass of the flywheel, the engine doesn't have enough momentum to give the ignition system time to catch the motor before it dies. It seldom, if ever, does this if the A/C is not operating. Does anyone have any suggestions on how I can keep my flywheel and still enjoy the benefits of air-conditioning?

RE: 964 911-C2 engine stalls due to low mass flywheel
 

I think the only sollution is to go with a new fly wheel..... sorry:(

RE: 964 911-C2 engine stalls due to low mass flywheel
 

Actually this can be fixed with a proper program. The issue is the ISV can not move fast enough based on the 8X8 grid in the dme. A properly tuned ECU chip will correct the issue. You can also adjust the ISV to help however this is more a band-aide then fix.

RE: 964 911-C2 engine stalls due to low mass flywheel
 

Thanks for the response. I have an AutoThority chip for the car which I had replaced with the original stock chip. I had thought maybe the stock chip would not experience the same symptoms.

I think I'll put the custom chip back in and investigate tweaking the ISV to see if that will do the trick. If not, perhaps AutoThority can modify the programming on the chip to compensate for the LM flywheel mod.

RE: 964 911-C2 engine stalls due to low mass flywheel
 

Yes, they can retune them. We do our own so we do not work with them directly anymore. I do know from past years they have the L/W flywheel fix.