A couple of months back my tach started reading approx. 2000-3000 rpm's above what it's actually running at, actually may be more. When I run WinALDL it reads the actual RPM's just fine. The tach doesn't bounce around or anything, just steadly reads WAY over the actual RPM's.

Anyone know what causes this to happen?

Thanks in advance!

-Josh :lala:

 

Awww, come on. Someone must have had this problem before, at atleast knows whats going on!

 

My tach is doing that too and as of yet, no one on this board has given me any useful information. I replaced the coil, cap & rotor with MSD components, but it still does it. Hopefully I can get it fixed soon.

 

The only thing I can come up with is the actual tach on the dash (the electrical unit) is bad....maybe a new instrument cluster will fix it.

 

Mine was doing the same thing, now its maxed out all the time. I don't know what causes it. I'm going to try a new cluster. I'd like the 145mph speedo anyway!

 

it is the guage.

it is VERY common. a new tach SHOULD fix it, but when buying a used one, it may have the same problem, don't be suprised if it does.

 

Stupid stock tach's! That thing had me worried for the longest...till I hooked my cable to it and ran WinALDL. Then I know the ECM was fine

 

obviously the ECM knows the engine speed, otherwise it couldnt run...

the problem isnt on the motor or ECM part... the problem is that the stock tachs wear out and break.

you can either send yours to be fixed ($$$) or replace it.

if i knew or could find how to fix it to be accurate again, i would tell ya... so far the only "tach hacking" was what someone posted about making a V6 tach work on a V8...