Not sure why or how to fix this, but the tach on an '88 GT is reading twice as many rpm as it should be. at 2k rpm it reads 4k rpm. Any way to fix this?

 

was the tach replaced recently from a doner car? if the car was a 4 cyl. then there should be a switch on the back of the tach that indicates either 4 cyl or 8 cyl. I know the older 4 eye tachs had this never really looked at the 87 up.

 

Not sure, just got the car. I'll look when I get a chance to work with it.

 

There's a switch on the rear of the tach. As raven_ghostwolf said, it's was probably from a 4-cyl.

Easy removal/fix.

Cheers!

 

Yep, it's setup for the ppr on a 4cyl, switch it to the V8

 

thank you guys

 

did it work cuz i have the same problem? im gonna look at it right now tell you what i see...

 

ya i got the same problem......., twice the rpm it really is. I also went from a 140mph to a 85mph speedo and now it reads wrong. I figured it wouldnt make a difference. The whole cluster is out of a 91, 4 cyl.
I like the 4cyl gauges better it keeps me out of trouble. LOL

 

Yes it does matter. If you change the speedo, you will have to change the speedo gear to correct the mph. Also, as numerous guys have stated already, the tachs in these things were the same whether it be a 4,6, or 8 cylinder. There was a switch in the back and that's all it takes to fix it.