Tach doesnt work..
 

so i my tach/gmp does not work. the guy who had the car before me put spme after market dash tach as he was trying to make a street racer. that quit working too. i dont know if the origional is trashed or if the kid wanted the dash tach to look cool. im needing to fix the origional. any tips before i dig in? im still trying to figure out how to get to it.

You have to remove the center "cluster" as one unit. Make sure the wiring is intact. The tach may or may not have a shift light depending on when in 84 it was made. Mine has the shift light and the tach is intermittent. I bought a non-shift light unit but the internal wiring is all wrong and it causes several other gauge problems so make sure what you need if you need to replace.

There can be some grounding issues and it won't hurt to add an additional ground to the cluster behind the dash. I added one and some of the other gauges seem to work a little more "reliably."

These units seem to either be OK or are just junk. They can be rebuilt but it usually is cheaper to find a used one and replace. I have the non-shift light unit sitting on the corner of my desk if you need it, I paid $50.00 for it.

PM me if you have questions or I can help.

ok, 2nd question. dude put a hard dash cover on the dash. do these just slip off? nothing on my cluster works exept for 1 bulb and the spedo. i think before i tackle this i should get some bulbs and the gears to fix od. anyone have any bulbs?

Most of the dash covers come off or will not need to come off to remove the cluster. See our host for bulbs. As to the gear, most have "slipped" and can be pushed into the correct engagement and then secured with a spot of epoxy. This worked on mine, been fixed almost 2 years with no problems.

I think you can find instructions on the cluster removal and the odometer gear repair at Clark's Garage under his on-line shop manual section.

Hey Matt,

If you need help finding a new tach for it, let me know and I'll see what I can find.