Tach Attack Help!
Tach Attack Help!
Author
Discussion

lear60man

Original Poster:

23 posts

285 months

Thursday 17th April 2003
quotequote all
My Tach is working then dead etc. It jumps around then dies. Next trip it works fine. Where is the sending unit so I can check the gound? Any other ideas would be most helpfull. Thanks

lotusguy

1,798 posts

281 months

Thursday 17th April 2003
quotequote all
What model year???

cnh1990

3,035 posts

287 months

Thursday 17th April 2003
quotequote all
I think he has a 95

lear60man

Original Poster:

23 posts

285 months

Friday 18th April 2003
quotequote all
Sorry about that, it's a 1995 S4.

cnh1990

3,035 posts

287 months

Saturday 19th April 2003
quotequote all
Looks like no one is chiming in on this one.

The 1st lead to the tach is connected via the front wiring harness to the direct ignition module which in turn connects to the Electronic Control Module (engine management).

The other lead is wired through the ignition warning tally light and vis the front harness to the alternator.

The Tach is grounded to the dash pod ground.

It is suspected that the tach itself is broken or the movement is malfuctioning.

Do you know how to remove the pod cover by releasing 10mm bolt and phillips head screws? If you do not have done this before or know how, scuffing of the leather of the pod cover and stereo module cover could occur.

If you know how this proceedure is done remove the cover and then the tach.

Take the tach to an auto gauge and instrument repair shop to be checked and calibrated. You may have to post it to a shop if there is not one locally.

This will give you good start. Do you know of anyone with an SE or newer 4 cyl? You could temporarily install your tach into another Esprit to see if tach itself is broken or if it is something else. It may save you both money and time if you do this.

Also if you have freescan hook up a laptop to the ALDL connection and bring up the tach on laptop to see if you are getting a right reading from ECM.

Good Luck,
Calvin



lear60man

Original Poster:

23 posts

285 months

Sunday 20th April 2003
quotequote all
Thanks Calvin! At least I know where to start. A couple of months ago my turbo boost needle was doing the exact same thing. The screw holding the ground wire had backed off about 4 twists. Thanks again, I'll post my findings and try to keep the circle of information flowing.