Tachometer Repair
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,783
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From: Mays Landing, NJ
Tachometer Repair
When I bought my 1991 Coupe I knew the tach didn't work, but since it's an auto trans wasn't important to me. I have become curious as to what could be the cause of it not working. Several threads that I have read here talk about a bad tach filter or a resister on the circuit board going bad. While I already have a list of improvements I'd like to do, at some point in the future it will be something I'll probably like to fix. Anyone have any experience with this?
Team Owner
Joined: Sep 2003
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When I bought my 1991 Coupe I knew the tach didn't work, but since it's an auto trans wasn't important to me. I have become curious as to what could be the cause of it not working. Several threads that I have read here talk about a bad tach filter or a resister on the circuit board going bad. While I already have a list of improvements I'd like to do, at some point in the future it will be something I'll probably like to fix. Anyone have any experience with this?
Most everyone with a '90 - '91 has had this experience
Last edited by WVZR-1; Nov 12, 2018 at 05:30 PM.
Pro
Joined: Apr 2008
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From: Pine Barrens New Jersey
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,783
Likes: 579
From: Mays Landing, NJ
Before I turn the key on the needle is at the bottom, but I never looked to see if it was at 0. I do notice that as I accelerate the needle pegs above 6000. On my next drive I will pay better attention. The car does have C68, how can it be used to confirm RPM?
Team Owner
Joined: Sep 2003
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***don't worry about where it parks with KEY OFF (It can be anywhere)
C68 - push FAN + and FAN - simultaniosly for a few seconds and display should show 00 I believe, push AUTO FAN and it should display C68 codes. After code display if you use FAN + or - various paramaters are available. Toggle to 6 I believe and hit AUTO FAN - RPM will be the display /25. If I get a chance I'll copy the entire list of values. Do you have the FSM?
Last edited by WVZR-1; Nov 12, 2018 at 08:31 PM.
