4k Tachometer Reading With Engine Off

[chspyder]

Help, I have a 92 XLT 4.0 V6 that reads 4k on the tech with the key on and engine off , when I start the engine the tach goes back to 3,500 then as i rev it a little it goes up from 3.5 at the regular pace as the engine feels to be 2.7 rpm.

Please let me know if you have any ideas, also how to track the tach to the engine, I have trackked to the computer

Thanks

 

[DeagleDave]

have same problem. from what i've been told it's time to replace/repair the tach.

 

[chspyder]

Have you done this and what happened?
My problem comes and goes with the cool/cold weather, the colder the better it is.

I have taken apart dash and looke thourghly at the tack and it looks ok.

I am going to try to check the main tach lead in the dash to see if it is running with no problems.

Anybody have any ideas?

 

[chspyder]

Ok Just fixxed this it is simple, take apart the dash and pull out the tach, then clean all contacts, and add some wd40 to the coil of wires, then juggle it, and add more WD40 and the put it together.

Then Boom It Works!

 

[DeagleDave]

explain juggle it?

 

[chspyder]

You just add some WD 40 and move the needle a lot, up and down, be careful not to go around the dial.

Also if anyboy needs a tach, I have a spare 92 explorer tach that retails for 290 I paid 125 for it.