1992 3.0, And as you can see why... somebody tapped into the black wire for aftermarket Tach operation. The wire is broke off flush. I scratched around on the material surrounding wire and it's hard as a brick. Can't dig the remaining piece out. Truck doesn't run any different and only thing that doesn't work is the Tach. Must the wire be fixed, what else does it affect? Any other way to fix besides splicing in another connector?

 

PM me your address and I'll mail you a good plug with several inches of pigtail that you can splice in.

 

Many thanks for the offer, but does that wire even impact anything else? If not then I won't fool with it so the other four wires stay intact.

 

Not sure what the ECU might use that signal for.

Possibly for RPM limiter. Possibly for part of EGR control, IDK??

 

This rpm signal goes to three places in the schematic I have..

AC amplifier
Dash tachometer
Diagnostics port

The TCCS computer on the 3vz controls the ignitor at all times, so the ECU always knows the RPM, and this is an auxiliary circuit used for the "industry standard" ground switching tach signal.

 

So maybe the wire only went "to tach" ?

 

From my 88 vzn manual..

 

I understand now. Might try to solder or tack it back somehow on a warm day. Gonna pm millball too. Thanks y'all !