I can be at a red light or driving down the road and my tack needle will simply go spastic..... Any ideas what can cause this? A sensor?

 

I've gotten the jumpy tach before too, but it hasn't happened in a while, usually on startups on a cold morning if I remember right. Now my aunts 2002(?) Expy did it all the time, it never stopped working but it was just shaky.

 

I have a 2000 Ford F150 with the 4.6L engine and auto trans. Sometimes when I shift out of N into D the tach will jump peg the otherside of the tach. I don't know if this is what you meant by spastic, but the dealer told me it was the computer resetting its self.

Maybe some of the other members may be able to comment more.

 

The tach sometimes pegs to 6000 and back to 0....but back and forth real fast and sometimes it sticks on a setting and then starts jumping around again.


Has anyone encoutered this before? Any guesses on the problem?

I have a 2001 crewcab 5.4 engine

 

I've never seen that before I've seen the gauges do that but its after I've disconnected the battery or run it down really good. The only erratic thing I've ever see the tach do it act sticky or shaky.

 

Just to toss something out ( don't act on it yet donnie81, until you get another yea or nay ), could this be from a dirty or loose edge connector at the HEC ?

I can't say as I have read about this one straight away, but this is about the only thing I can think of that might be an "easy" fix.

Just want to get some additional input from others, and if I get a chance, to try a search on it here.

 

Thank You "SSCULLY" for your input, I will check it out and let you know if that was it or not.

 

Zaairman I will check out a loose or dirty connection on Thursday.

Thanks for your input sir !


Donnie81