1986 Carrera stops dead and restarts for no apparent reason
My 911 (130,000 miles but well cared for) suddenly has decided to do the following: turn itself off and on. It does this about every 90 miles or so. Does not matter how fast I'm going, what gear. It's as if the ignition is turned off. The car then, through momentum, starts itself up again. This is tolerable in 5th, but in 2nd, car jerks forward, and it's obviously bad for clutch. Battery is new. I have checked for corrosion on cables and grounds and sandpapered. I have tape-rapped anything I see where tape is old. The stoppage is not triggered by bumps, or heat of the engine or anything that I can find. Any ideas on what's up would be very much appreciated.
This intermittent type of problem is hard to diagnose ( like chasing a ghost), but you are looking in the right direction. Loose connections, corrosion at the engine/transmission ground strap. Check the ground connection from the battery to the chassis and the ground connections from the engine/transmission to the chassis. I would check the connection to the ecu as well to see if there is any moisture intrusion that might cause corrosion. Sometimes corrosion is not evident until you pull the connectors apart and inspect them. Good luck
Also check the wiring behind the ignition barrel. Could be that at some point in its history somebody tried to hotwire the car and the repair is not perfect.
Check your DME Relay.
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