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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Tach Problem

  • Thread starter Thread starter snoboardcore
  • Start date Start date Apr 28, 2005
S

snoboardcore

New Member
Mar 30, 2005
276
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0
New Hampshire
Apr 28, 2005
#1
  • Apr 28, 2005
  • #1
Hey guys my tach jumps all around from like 3000+rpm when u really hammer into it. The tach will go to 5 then 2 or 3 or 6 then to 3 anyways it jumps all over the place. I look at my monster tach and thats does the same thing. What do you guys think it could be? Possibly my coil?
 

95opal

5 Year Member
Nov 16, 2004
449
20
39
Apr 28, 2005
#2
  • Apr 28, 2005
  • #2
sounds like you have a bad ground somewhere.check ur ground wires its more than likely your culprit
 
S

seijirou

Founding Member
Aug 15, 2002
2,417
4
48
DFW
Apr 28, 2005
#3
  • Apr 28, 2005
  • #3
Hey rather than making a new thread I might as well post my quesion in this one.

My tach reads too high. The car is an 86, but the interior is from an 87. I think somewhere in the wiring something is missing, crossed, or something.

The best way I can describe the problem is if you can imagine what would happen if you put a tach calibrated for a 4cyl car into an 8cyl car. It just reads way too high, and sweeps way too fast.

I do know that the 86 tach has a selection switch in it for 4,6,or 8 cylinders. The 87 doesn't have this feature. I think maybe there is supposed to be resistance in the tach signal wire that I don't have, but I'm really only guessing. And I don't know where the tach signal wire actually is.
 
S

snoboardcore

New Member
Mar 30, 2005
276
0
0
New Hampshire
May 14, 2005
#4
  • May 14, 2005
  • #4
where are the ground wires located
 
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