Well I bought a autometer 5 in tack. Just saw it and bought (damn impulse buys). Well i know its only 4 wires but something went wrong. Got the dash light the power wire and the ground. Found what I think is the tack wire and the tack dosn't work. The tach wire a yellow and blue striped one is close to the driverside door under the dash right?

 

There are several yellow wires with blue stripes in that area. According to the diagram they are all supposed to be tach wires but I've found issues trying to get a tach signal from them. The best bet is to get it from the cluster harness directly, or pull it from the test connector at the coil.

 

so just pull the cluster out? and use those?

 

Didnt work

 

That's a bit odd. Have you tried connecting to the connector at the coil, or the coil negative?