tach going crazy
Thread Starter
Intermediate
Joined: Aug 2005
Posts: 27
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From: ROSEDALE VIRGINIA
tach going crazy
I have a '92 6-speed...I have noticed the tach hand kind of jumping around for the last couple of weeks, now it quits working and drops to 0 and then a few minutes later it works again then back to 0. Is there anything it could be other than the cable?
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
The '92 tach is all electric; it doesn't have a cable.
If you are seeing no other problems (like the ASR light coming on, or trouble-lights), my guess is the tach itself is defective.
If there are other symptoms, I would guess the tach filter is the problem.
Tom Piper
If you are seeing no other problems (like the ASR light coming on, or trouble-lights), my guess is the tach itself is defective.
If there are other symptoms, I would guess the tach filter is the problem.
Tom Piper
Burning Brakes
Joined: Nov 2000
Posts: 1,012
Likes: 1
From: Bowie MD
It could be the tach filter as mentioned and that is a cheap and easy fix if it is. Follow the wire from the Distributor towards the firewall. you will see the tach filter and its easy to replace. 
However, if it was like mine. The tach itself is dead. Mine was flaky too for awhile, then quit all together. By following the instruction GM manual, I was able to remove the tach, but had to also drop the steering wheel, which means the battery has to be disconnected so the airbag doesnt go off. I found a replacment tach on ebay. Be careful though, although the 1990 to 1996 all look alike there is a break point where they do not interchange electronically. I know the 1990 and 1991 are alike. The ZR1 tach has a higher rev limit on it, but usually they cost more. It was going to cost like $225 to get my original one repaired, so I just bought a used one on ebay and hoped like hell it worked. It did and that has been 2 years later. The odometer mileage is stored in the computer, so you do not have to worry about that either. I also replaced all the bulbs in the back while I had it apart. Good Luck.
However, if it was like mine. The tach itself is dead. Mine was flaky too for awhile, then quit all together. By following the instruction GM manual, I was able to remove the tach, but had to also drop the steering wheel, which means the battery has to be disconnected so the airbag doesnt go off. I found a replacment tach on ebay. Be careful though, although the 1990 to 1996 all look alike there is a break point where they do not interchange electronically. I know the 1990 and 1991 are alike. The ZR1 tach has a higher rev limit on it, but usually they cost more. It was going to cost like $225 to get my original one repaired, so I just bought a used one on ebay and hoped like hell it worked. It did and that has been 2 years later. The odometer mileage is stored in the computer, so you do not have to worry about that either. I also replaced all the bulbs in the back while I had it apart. Good Luck.
