I notice that the guages on my dash are off. The tech pins itself when you take off, also the oil presure guage is also pinned up when you start the engine. The speedometer is off by 10 mph.

Could this be a bad ground or are the guages just bad? Thank you

 

the speedo is calibrated for 25.7 inch tall tires.

the gauges weren't all that accurate to begin with, and pretty common to be screwy these days. If you google "tachman" you'll find a company that calibrates gauges, but I bet its expensive.

There's also a thread on replacing resistors in the circuit board yourself, but I personally didn't have much luck with that.

 

Thank you, will look it up and give it a shot..

 

I know grounded sensor wires for some gauges peg the needles, but don't know if that applies to the tach as well. Worth checking for sure. Sent PM for another option if interested