Unreliable tachometer

[Murray S]

Recently, my tachometer has developed a problem where it doesn't always show engine RPM's, especially at lower speeds. If you rev the engine to higher RPM's, the tach will usually kick in.
As I have not gone in behind the instrument cluster to check how it works, can someone tell me if it runs mechanically off a cable, or if it is an electronic feed?
My guess is either the feed or the gauge is sticking, but I would appreciate hearing from someone in the know!

 

[Garth]

Electronic feed.

 

[1993Limited]

I am having the same problem in my 1995 xlt 4x4. I hade to change the alternator out this past weekend and it seemed to fix the problem. But a day later the problem returned. Where does the tach get its signal from? This is a small issue but it is one that drives me crazy.

Thanks
david kindred

 

[Christobal65]

Sorry to dig up an older thread but I too have this problem my Tach on my 92 is stuck at about 3800PRM and only reads correctally when i go above the point where the tach is stuck at. I have seen a couple of other 91-93's with this problem and was wondering if there was a quick fix for it.

 

[RedXplr]

My 94 has a similar problem, reads about 1000 rpm low most of the time. If the weather is warm or I have been driving for a while sometimes it fixes itself.
If someone knows what it would take to fix it, that would be great. However with the truck being an auto and 10 years old, I dont see much point in putting any time or money into this problem.