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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Tach Going Reverse - Help Please

  • Thread starter Thread starter citmov
  • Start date Start date May 12, 2012

citmov

10 Year Member
Sep 25, 2009
632
12
49
Chi-town
May 12, 2012
#1
  • May 12, 2012
  • #1
So here's what's happening...
when I turn the key to acc position my tach jumps to 500. Then after I start it everything seems to appear okay. Idle sits at 1100 and after it warms up it drops below 1000. But when I rev the RPM to anything over 1500 the tach goes backwards below zero.

Here's a vid of what's happening:
http://youtu.be/L9Qbixt9fXg

Some more info on my car:
- 93LX 5.0
- No aftermarket tach
- I had a shift light attached when I bought it but I took it off to see if it was wired incorrectly but that did nothing.
- MSD dizzy (I had an oem before but did the same thing)
- MSD coil (this has been on every since I've had the car)
- New Ford racing wires
- New plugs

Any thoughts on what to check or what it could be? Any help would be appreciated. Thanks!
 

jrichker

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May 12, 2012
#2
  • May 12, 2012
  • #2
The circuit board on the back ot the tach is toast. Good luck in finding a circuit diagram for the tach circuit board. I haven't been sucessful, but then again I haven't spent hours looking for it. If you can find a circuit diagram, for the tach circuit board, I will be glad to help you fix it.
 

citmov

10 Year Member
Sep 25, 2009
632
12
49
Chi-town
May 12, 2012
#3
  • May 12, 2012
  • #3
Thanks jrichker for the reply!

So basically find another cluster?
 

citmov

10 Year Member
Sep 25, 2009
632
12
49
Chi-town
May 14, 2012
#4
  • May 14, 2012
  • #4
It was the cluster (specifically the tach). Swapped out the cluster and all is well. Hopefully this can help someone if they run into the same problem.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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234
Dublin GA
May 14, 2012
#5
  • May 14, 2012
  • #5
I ws hoping you found the tach board circuit diagram...

Glad you got it fixed.
 
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