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[Cbass]

Although I hate to double topic, I am also interested in the late 931 digital ignition. What are the major components of the system, and does it still have a distributor or what?

[Smoothie]

I have an '82 931. It has a distributor, but it's only used to direct the spark to the correct cylinder - no vacuum advance/retard on it, no centrifugal advance and no hall effect sensor built into it and timing isn't set by it either. There's a crank sensor that picks up timing from the flywheel. Behind the radio on the "hump" there's a DITC (digital ignition timing control) box. It has a vacuum line plus two electrical connectors attached. One is the crank sensor and the other is a rectangular multi-pin connector that needs to be reseated on rare occasions to correct a "rough running/tach flopping around" condition. That's about all I know (/have needed to know) about the digital ignition. There's got to be more though...

Page 288 of the Haynes (US edition) shows most of it.

[ This Message was edited by: smoothie on 2002-06-07 16:30 ]

[John H]

The main components have been listed by smoothie.
The total system comprises: an ignition control unit mounted on a heat sink down on the front left fender behing the head light,a temperature sensor on the throttle body, the flywheel sensor (pulse transmitter), the vaccume pick up just behind main chanber on the inlet manifold, coil (of course) distributor which as smoothie mentions is just to dump the spark to the plugs.

[ This Message was edited by: John H on 2002-06-07 15:44 ]