Tachometer wiring issue

[cmc140]

I was hoping someone might be able to guide me in the right direction on a tach wiring issue. The car is an 86 930 with recent MSD install.

Here are the steps I've taken so far:

1. Verified continuity on the black/purple wire between the 6-pin CDI plug and the engine connector plug.

2. Verified an open between the engine connector and the black/purple wire at the back of the tach.

3. Verified if I hook the MSD tack output directly to the tach with a jumper wire it operates properly.

Is there another connector between the engine connector and the tachometer that could be disconnected? Or is it just a broken wire in the main harness? I'm not sure how to even access the main harness to run a new wire, but it seems odd to me that it'd be necessary.

Any help or ideas sure would be appreciated.

Thanks,
Chris

[timmy2]

Check continuity from 6 pin all the way to back of tach.
Could be a loose pin or socket in the 14 pin connector. Bad solder joint or a broken wire.
Check continuity from male 14 pin to back of tach.

[cmc140]

Originally Posted by timmy2

Check continuity from 6 pin all the way to back of tach.
Could be a loose pin or socket in the 14 pin connector. Bad solder joint or a broken wire.
Check continuity from male 14 pin to back of tach.

Thanks for the reply.

The 6- pin to the back of the tach is open.
The 14-pin to the pack of the tach is open also, when testing with my meter.
The 6-pin to the 14-pin has continuity.

So, somewhere between the 14-pin and back of the tach is where my issue seems to be. I was curious if there is another connector the black/purple passes through that I might check? I didn't see anything behind the gauges, but it's hard to see anything back there.

Thanks again,
Chris