Flywheel Differences - 986 Forum - The Community for Porsche Boxster & Cayman Owners

BYprodriver · 03-15-2015, 05:13 PM

I believe any M96 flywheel will bolt to any M96 crankshaft, & I believe the ring gear with reloctor wheel, is interchangeable among any M96 dual-mass flywheel. I believe this because I don't know any reason they wouldn't be, given Porsche's goal of making as many parts as possible interchangable for all their vehicles. Jake Raby recently hinted that the flywheels are not interchangable for different engine sizes, due to different dampening requirements.
So I don't think you have solved your problem unless you have a bent "tooth"

Gelbster · 03-15-2015, 05:27 PM

Now for some WAG before the evidence is offered:
Would a badly worn (= wobble & or excessive rotational free-play) DMF cause the idle problem? If the car has over 70k miles(??) ,the DMF is due for very careful inspection & probably imminent replacement anyway.
DMF wear may explain why the Crankshaft Position Sensor is giving fluctuating readings ?

Reebuck1 · 03-15-2015, 05:39 PM

I do not believe the 98 or 99 five speed transmission will allow a Boxster S DMFW
to fit or run properly in the smaller transmission housing. I AM NOT 100% CERTAIN THOUGH. The reason I say this is when I installed my 996 3.4 motor in my 98 Boxster I was unable to get the DMFW from the 996 to fit in my five speed
housing and I had to go to a Boxster S six speed to get everything to work. I do think it might fit in a 987 five speed housing.

Duezzer · 03-15-2015, 10:15 PM

The shop I took it to said their diagnosis is that the new flywheel I installed has an issue and that is why the readings are not correct from the Crank Position Sensor - They wanted another 7 hrs to pull it apart and inspect. I am having a tough time with their diagnosis so decided to bring the car home and do the inspection myself. I understand how they got there. They were recieving week reading from the sensor and when they modified it so it sat closer to the teeth they got a better signal, car started idling but timing is out of whack and was not drive-able.

There is a new (possibly damaged, not made correctly or incorrect) DMFW in the car.