Tach is acting crazy

[malcolm2]

'01 mountaineer v8 awd.... I travel about 15 miles on the interstate each morning. I usually use cruise control. Sometimes I look down at the tach and it will jump from 2000 to 3000. No change in revs, just the tach. Sometimes it lasts for 3 or 4 seconds and returns to normal, sometimes it stays there 'til I exit and it actually down shifts on the exit ramp. Happens when not using cruise too.

Any ideas?

No CEL, not an operational problem, just a crazy tach. IIRC last year I replaced some, maybe all of the coil packs, i will have to double check that.

Thanks,
Clark

 

[German Engineer]

I have that exact same thing happen too, but only extremely sporadically. I haven't bothered with it yet, because it just happens so rarely on mine.

 

[RandomNerd2000]

Might just be a cluster problem, not uncommon on a 2nd gen afaik.

 

[rasouth]

I have a similar problem. Mine goes to zero and only occasionally reads the RPMs. I was told it was an electrical issue with a sensor, maybe around tranny, not sure.