[richeyb]

I had posted earlier about gettinghelp fixing an intermittent TACH. It was suggested corrosion on the wiring connection.... Does anyone know where I can find that connection and how to clean up the corrosion....? I took a look and could not make a guess where it was...

[Phager]

According to my wiring diagram for my 91, it appears that the tach recives power from pin 4 on the one of the connectors to the cluster, however since that power feeds the other guages, I suspect the poor connection isn't there. However there could be a break in the circuit tracing on the circuit board on the back side of the cluster, which could lead to an intermitent issue.

The other spot to check would be the connection on the engine control computer, which is located behind the right kick panel. On my 91 the signal wire is listed as tan with a yellow tracer located at pin 4. Make sure that connection is tight and the wire is fully seated in the connector, and hopefully that will take care of the issue.

Also make sure your grounds to the EEC are nice and tight and clean. A bad ground can lead to all sorts of hard to diagnose intermittent issues.

Good Luck!
Pat

[PerformancePartsInc]

Clean connections but the final verdict will probably point to the tach itself. We have been selling more OE tachs and peripheral gauges for '87-'93s, due to simply burning-out, than ever before.

[TOM RENZO]

Totally correct we replace loads of factory tachs. When they get intermittent the tach head is probably shot.

[richeyb]

Anyway to check the tach or do you do that by replacing it and the new one works?

[richeyb]

Thanks I'll check into it this Saturday and see if I can find those diffent pins....