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uwanna uwanna is offline
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Join Date: Jan 2009
Location: Marietta, Ga (Atlanta)
Posts: 2,970
Quote:
Originally Posted by cabmando View Post
I'm going to get under my car this evening and check that strap. I know I tightened it but I'm going to recheck. I was thinking there was nothing I unplugged that would effect the tach but there has to be some connector that sends signal back to the Motronic for it to process the signal. I'm going to go over the wiring schematics and recheck all my connectors. It has to be something simple.
Think about it for a moment, on earlier cars with CDI ignition, the tach signal is developed IN the CDI unit. Same for DME, as the "CDI" is contained within the DME box. The signal is not driven by any sensor on the engine.
The tach pulses are sent from the DME on DME connector pins #4 and #11. #4 blk/violet wire, #11 blk wire. These wires run direct to the rear off the tach. Pull the DME connecter loose and check their continuity with a multimeter to the rear of the tach.
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'80SC Widebody 3.6 transplant Anthracite "The Rocket"
Long gone but still miss them all:
'77 911 Targa, '72 BMW 3.0CS Coupe(finest car I ever had!)
'71 911T Coupe White, '70 911T Coupe Blue
'68 911 Coupe Orange, '68 911L Soft Window Targa
Old 06-18-2015, 05:36 PM
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