Why Does my tach not read correctly? Some times it reads 1500, and other times it reads 4500. I can be at idle and it is at 4500 or doing 80 in 4th gear reading 1500. It will sit at 1500 all day then quickly jump up to 4500, then just drop back down later on. Any Thoughts?

john

 

MSD etc. installed?

 

Are you refering to the MSD Tach Adapt kit?

 

Just replace the stock ignition module with a brand new one, didn't work before or after. any thoughtss??

 

Has anyone ever had to fix there stock tach before????? I am trying ot keep the interior all original, so i am less likely to get her broken in to.

john

 

They break all the time; but not usually like that. That sounds more like an intermittent connection somewhere.

Have you checked the cluster's ground? Taken a look at the flex circuit board on the back of the cluster?

 

are our tachs inputs electric or mechanical???

john

 

electric

 

You might want to check the unit on the back of the tachometer in the instrument cluster.

 

so you are saying to take off the cluster and clean the circuit board on the back with like isopropyl alcohol and see if that works?

john

 

Unit????

 

Do you have any aftermarket spark boxes installed? If not check your connections, if you do you have to get the filter.

 

I am sorry bud, what do you mean by after market spark boxes? As far as i know the ignition is all stock.

john

 

Yes, it is the little unit that sits on the cluster behind the tachometer gauge and has the tach needle attached to it.

 

ok, how do i test it??

 

Check this. In this test, what you are actually testing is the voltage going to the tachometer connector on the instrument connector located on the right side of the dash. If the voltage is correct and the tachometer is reading wrong, you replace the tachometer. See the third picture for the pin number and location. BTW, I forgot to mention the wire for the tachometer is the white wire coming of the gray connector on the ignition coil. Before going to the instrument panel it splits off and goes to the ESC module.

 

page 2

 

page 3

 

sweet,

if you don't mind, what manual are you using for this.

john

 

I don't mind, it is the GM service manual for the 1989 camaro's.

 

any place i can find a pdf copy of this online?

 

You have a PM, John.

 

cool, thanks bud, now i just have to figure out were in the heck my pm inbox is, especially now that i am athome on my dial up connection. Damn, i almost miss being at work with our T-1 Connection..

john

 

Hey John,
Look at the bottom of your post and you will see a button there that says PM. click on that and then click on Private messages in the upper right side of the screen.