Tach quit working

[import racer]

Hey guys,so I went to work this morning and worked fine.went to come home and when I started the car my tach wouldn't work.Is there a fuse for it.

[Gemini2003]

The tach is manually controled by a cable to the tranny I think.

See if it's come loose I think it's runs to the diff on the Tranny.

[import racer]

no cable for tach.

[import racer]

So i changed the resistor on coil and that made no difference.The dizzy doesn't make any noise,and when i start it up or shut it down the tach jumps.I think it might be my coil or the tach itself.what do u guys think.

[Jafir]

I've seen bad tachs and I've seen bad igniters cause the tachs to do funny things. The TEC distributor/igniter on most lxi is pretty robust though. Usually a bad igniter will cause rough running too.

(For what it's worth really really old Hondas had a tach driven off of a cable from the cam shaft)

[Legend_master]

The tach is manually controled by a cable to the tranny I think.

See if it's come loose I think it's runs to the diff on the Tranny.


That would be the speedometer.

Import racer, good chance it is your cluster. If not it can only be the tach or wiring.

[Dr_Snooz]

It's hard to say. It's possible that the igniter is to blame. Check out post #11 in this thread for a way to test it (thank you to member HLW for finding the test for me). It's possible that it's the coil, so check that as well with the test in the '89 USDM manual. If those two things check out, then it's most likely the gauge. Because you aren't having any running issues, I'm inclined to agree with Legend_master that it's the gauge.

[import racer]

Well i haven't had any problem with it before,it just stopped working.I'll check the coil tonite,I have other tachs but no clusters.I know some are different so not sure if i have one that will work.

[import racer]

I have an aftermarket one I could use if that don't work out.

[Legend_master]

You could at least use the aftermarket tach to determine if it is in the distributor or cluster.

[import racer]

Yeah but I found the after market one showed less the the factory one.Anyway went out to start car this morning and the tach stayed at zero,then it just started working again.

[lostforawhile]

the tach is easy to swap out in the cluster, just screws that both hold it in and act as terminals, I know there are two different clusters, but I think the tach can be swapped to any of them, don't mix up the screws when removing them, as they are different lengths

[Dr_Snooz]

Pulling the cluster in a 3g is relatively painless. It can be a nightmare in other cars. Like the 4g. My 1g was also a bastard. My white truck was impossible.

[Legend_master]

The cluster comes out in less the 10 minutes if you know what you are doing. Maybe 20 minutes if you are learning.

[import racer]

Well It's still working,might put in aftermarket one this weekend.Which wire on the coil do u hook up.

[AccordB20A]

the blue one is the tach signal wire

the stock one will read lower than the aftermarket one as the stock ones not terribly accurate

[lostforawhile]

mine always matched pretty well, i'm thinking there is a potentiometer on the board for calibration

[lostforawhile]

The issue could even be inside the coil, there is a resistor between the output side of the coil and the blue wire going to everything that uses the tach signal, its INSIDE of the coil body, dont confuse this with the radio capacitor, oh the AC also has a rev limiter that depends on that blue wire, if you overspeed the compressor the delay unit disengages the compressor clutch, compressor rpm is lower then engine redline