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Tachometer pegged out

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Old Nov 19, 2008 | 12:45 PM
  #1  
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phonypony05
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Question Tachometer pegged out

Hello to all, My wife came home from ER last with our son and was trying to tell me her problem she was having. She says the Tachometer was pegged out all the way to the right side, and still pegged out when engine is shut off and no she was'nt racing to get home . Any info would be helpful to us, I did disconnect the battery this morning and it did set back to normal to the left side. and has'nt pegged out since.Thanks Paul
Old Nov 21, 2008 | 11:50 AM
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Guess there is no real Motorheads in the entire Forum that can answer any of this.?
Old Nov 21, 2008 | 10:53 PM
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Well no need to go insulting people on here, that will get you no answers what so ever, but It would seem to me that it was just an electrical short circut
Old Nov 22, 2008 | 08:24 AM
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I could explain it but I wont.
You would have to be a 'motorhead' to understand it.
And no it was not an electrical short.....
Did you get the unwanted underdash water dispenser option?
Maybe search the water leak TSBs?
Old Nov 22, 2008 | 04:07 PM
  #5  
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Is the car parked outside? I do know that there is a TSB about rain water getting to the inside of the car through the firewall. It is possible that some electronics where affected by the rain water.
Old Dec 12, 2008 | 05:45 PM
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yes there is a problem with rain/water being able to get in to the car through the firewall over on the passenger side. There is a fuse box over there where your feet would be. I would get that checked out.
Old Dec 12, 2008 | 06:23 PM
  #7  
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harraid5711
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Originally Posted by phonypony05
Hello to all, My wife came home from ER last with our son and was trying to tell me her problem she was having. She says the Tachometer was pegged out all the way to the right side, and still pegged out when engine is shut off and no she was'nt racing to get home . Any info would be helpful to us, I did disconnect the battery this morning and it did set back to normal to the left side. and has'nt pegged out since.Thanks Paul
I just went through this a couple of weeks ago so i think i can help. The problem is actually mechanical, not electrical. Once i pulled my instrument cluster and took it apart, i realized that the tiny gears right behind the tack needle were slipping, what happens is that when accelerating, the needle will move up fine, but won't go down all the way, so it'll be reading too high eventhough your engine speed is fine. Each time you accelerate, the needle goes up, doesn't come down, so on, and so on, until eventually it goes all the way around the clock so to speak, and it's reading off the chart. once you reset it, it'll work fine for a while, but will eventually mess up again.

The only fix is a new instrument cluster from the dealer. Mine was warrantied. All your odometer and other info is stored in the pcm so the cluster swap won't affect any of that.

Hope this helps.....
Old Dec 13, 2008 | 07:00 AM
  #8  
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I have heard that the odometer is stored in the cluster from other people? Did the dealership tell you this? Just curious.
Old Dec 13, 2008 | 08:31 AM
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Originally Posted by alloystang07
I have heard that the odometer is stored in the cluster from other people? Did the dealership tell you this? Just curious.

+1
I was under the impression that the OD info was stored
in the cluster and not the PCM. Can you elaborate on
where you got your info about the OD info being stored
on the PCM and not the Clusters data storage?

Just curious
Old Dec 13, 2008 | 10:13 AM
  #10  
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sure. as a way to test to make sure if it was the cluster. the tech grabbed a cluster out of another stang they had and plugged it in. all my information (odo, trip odo, mpg, etc) came right up......

also, i've heard of a couple of people who've bought clusters off of ebay and all their info was still displayed just fine.



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