Loose tach connection?

[scott_duerring]

My port tachometer started bouncing around this past weekend, engine running fine, so must be a loose connection as at times it will settle down.. I have good access behind the panel and checked all of the connections there but I get lost trying to figure where to check when I get into the engine room, does anyone know where the tach connections are on the engine side? I have 1999 8.2 MPI crusaders...

 

[rfdlou]

I bet the tach is going bad. Try swapping the right & left tachs at the dash. Just move the gray wire from one tach to the other.The wire may reach or use jumpers. Gray is the standard wire color for the tach in the harness.

 

[briang0]

My tach was doing the same thing. I read in here to try turning the selector switch that allow the tach to work on 4,6,8 cylinder engines and that fixed it. Turned the screw back and forth several times and all better.

 

[makomark]

The above posts have sound advice. they Grey lead connects to the "-" terminal on the coil. The other spot that can cause issues is the pin and socket in the main engine harness connector.