Problem with the tach not working

[jmvicp]

My tach stopped working a few weeks ago after i was messing around in my car. There is a green plug near the alternator that is not plugged in so im guessing that its the tach wire (?). If not, which wire is the tach wire and where does it go, i was looking all over that area to try to find a place that looks like it could plug in at, but couldnt find anything.

 

[FJM568]

um, you didn't happen to plug that green plug with the two white( or is it gray) wires into the black plug that is also hanging behind the alt, did you???

If so, UNPLUG them!!! You just plugged the tach wire into the fuel pump prime wire and once unplugged, the tach should start to work again(but the factory tach was never very good anyway)...If you didn't plug them into each other, then it sounds like your tach isn't working...hmmm...

 

[jmvicp]

Hmm, there was the green plug with 2 wires, looked like white, and it did have a black plug, with 1 gray wire plugged into it. I just unplugged them, havent tried starting it yet. But if thats the tach wire, then what is the single green wire with a black plug that is near the throttle? mine is unplugged. And one more thing, what do i do with the tach wire and the fuel pump prime wire, just leave them unplugged?

 

[jmvicp]

Wow, the tach works again, i guess you were right So im guessing the three are to be left unplugged?

 

[Steve Wood]

Yes, they are both test points and are not to be connected to each other.

 

[Michael Bottalico]

My tach goes all the way up when I start the car and I have a rough idle ..can't seem to find the problem

 

[Yamil87GN]

Mine is all the way up the entire time… any ideas?

 

[MikeS]

Mine is all the way up the entire time… any ideas?

This is a 21 year old thread. Best to start a new one. But to answer your question, there is likely corrosion on the copper connections on the back of the factory tach/ boost gauge. Mine are pegged all the time as well.

 

[Yamil87GN]

This is a 21 year old thread. Best to start a new one. But to answer your question, there is likely corrosion on the copper connections on the back of the factory tach/ boost gauge. Mine are pegged all the time as well.

Copy, thanks for your reply.

 

[GNVenom]

If the tach display and/or boost display goes to full scale or close to it, the unit is defective and needs to be rebuilt.

They all will fail in this fashion eventually. Genetic defect causes this to happen.

Caspers Electronics will repair it, or offer a replacement part.

Read about it: http://www.installationinstructions.com/FYI/tachboost.pdf

Boost/Tach Recalibration Svc (REPAIR SERVICE ONLY)

Boost/Tach Recalibration SvcREPAIR SERVICE ONLYDO NOT CUT THE WIRES TO THE TACH BOOST OR THERE WILL BE AN UPCHARGE OF $30!!!!! 1. REMOVE YOUR TACH MODULE FROM YOUR DASH2. PUT IT IN A SECURE BOX3. PUT A COPY OF YOUR ORDER SLIP IN THE BOX4. SHIP IT TO US 5. WE SERVICE IT 6. WE SHIP IT B

www.casperselectronics.com

or

REPLACEMENT Boost/Tach Module - 84-87 GN

NEW PRODUCT!Casper's Electronics has reproduced the boost / tach module for the Turbo Regals! This is a stand alone unit that has the same fit and function as the OEM unit utilizing modern day LED's, power supplies, and new components. While the LED sequence is a little different, due to

www.casperselectronics.com

 

[Hunter Dog]

I have installed a couple of Casper's replacement units. They are not exactly the same in terms of the colors of the lights/bar but they are close and a nice replacement, the only thing out there that I am aware of for this issue.

 

[GNVenom]

>>They are not exactly the same in terms of the colors of the lights/bar but they are close <<

The original LEDs are long gone and obsolete, so the next best colors were chosen. They're much more efficient than those 80s LEDs and will last forever.

 

[Hunter Dog]

I was very happy with the two sets I purchased and installed from Caspers. I would purchase again.

 

[Yamil87GN]

I think I’ll replace it with the LED one, my car is not stock anyways ¯\_(ツ)_/¯