Engine stalls / speedometer failure
 

Recently my Porsche 911 1985 had a full service. Shortly after that my speedometer / odometer failed to work (no relation to service). Pulled the speedometer out and send it for repair (common gear problem) through the Porsche dealer.
While the speedometer was out, the engine stalls now and then while driving (no gas and clutch down).
Today the speedometer came back (within 4 working days :), put it back in and the car drives flawlessly. Does this make sense?
Thanks,
Kees SmileWavy

There should be no correlation between your speedometer and the engine. Since you believe it is operating perfectly following the re-installation of your speedo, why not try pulling the speedo from the dash and marking and disconnecting the wires and re-test. I have driven several 911’s without speedo’s Installed, and none of them had issues.

Regards,
David

Thanks David,
Will try that 👍🏻