Does anyone know where the stock tachometer gets its signal? Is it from a computer? Where is it located?

I seem to have the same prob a lot have had in the past regarding a tach that does not indicate engine RPMs, but rather slowly creeps up to redline over the course of 25-30 minutes, even though the engine is fuctioning normally.

It looks like a classic grounding problem, but I have no idea where and I'd like to think its under the hood rather than behind that dash that will take 5 hours to remove!

Has anyone who had this problem found a solution? The Haynes manual is worthless in regards to describing the tach system, and this is my first computerized/fuel injected vehicle!

Thanks all

Mike

 

If you decide you need one, I can sell you an extra tach.

 

Don't quote me on this, but I believe the tach receives its power from the BCM (powertrain computer) located on the front passenger floor behind that small black kick panel. I'm not sure, exactly, what color wire it is...but I'm almost sure this is where the power is located. I know this, because, when I used to have a remote start, this is where they "tapped" into to control my RPM's when the car was remotely started. I hoped this helped any.

 

there is a wire that comes off of the ecu...if you go to www.maximadriver.com ( i think thats what it is) and then goto how2, then goto installing the super afc controller there is a picture of which wire is the tach wire. hope this helps