Whack Tach

[Mrb00st]

i was hoping i could get some input on this...

my 1988 SPG has a nearly non-functional tachometer. It works about a quarter of the time... mostly it just sits at 0, but when it is active it bounces around a lot. The car is running smoothly so I tend to doubt it's the ignition amplifier module, but I am wondering if there are any connections i should check to see if I can pin this problem down. Any help would be appreciated...

-James

[IronJoe]

James,

The ign amp module sits in the inner fender and can get hit with corrosion - I'd unplug it and check the connections, it's an easy (and cheap) test.

[Rodentmaster]

There is a little PCB circuit INSIDE the tacho that can get......

dry joints and from memory a little edge connector on the board which could cause grief.
It is close to torture to get the tacho apart without damaging the needle but it can be done.
Then there is the cluster left hand edge connector itself which could be worn or on the fritz.....

[Mrb00st]

checked the ign. amp connection - it was clean and shiny. cleaned up the whole thing, tightened it back down and hooked it back up - still no tach.

so irritating! This'll be my next project.