Can someone please tell me where I can find the tach sensor(s) ? My tach has been bouncing around lately, and I'm hoping its the sensor,s and not the gauge itself. If anyone has any info they can share , that wouyld be great.

 

On the top of the tranni.

 

thanks, but is that not the sensor for the speedometer? if it isn't then thank

 

There is one for the tach too.

 

 

That I can't help you with. I'm not sure which one is the tach and which one is the speedo unless I look at it. The manual should tell you.

 

 

Does the Ecu read the trailing crank angle sensor and puts out a tach signial . the signial out put can be found in the diagnosis connector .

 

Duboisr is right and it is not responsible for your tach bouncing. It is the fact that the tach itself is bad and need to be replaced. It is a common problem that is cured by replacing the gauge.

 

Yes it may very well be the gauge itself. But a mechanic at Mostly Mazda ( m2 performance ) did mention it could be the sensor(s).
My own reasoning for it not being the gauge is this. If the guage was in fact bad I would expect the needle to suddenly fall towards zero then jump back up to the previous revolution. But the particular problem I have with mine is that it occasionally zooms up, which varies from 200 k to 4000k. I have not been able to recreate the problem at will and it seems to do this randomly. Does my reasoning seem logical, or am I missing the obvious?
BTW, I read and reread Diboisr's post, and still do not understand his point.

 

Duboisr is a "she" dude.

 

there could be a problem with the solder point on the back of the board. check that. and like she said.... it takes the signal from the cas. you can find the signal in the diagnostic box on the driver side. the coresponding pin is IG-
read the wiring diagrams and see where the signal comes from.

 

RESOURCE should not be giving out answers for things he does not know.



Another reason to own a manual and read it.

 

 

That's caused from the lfd, lead foot disorder.

 

Very true, it has nothing to do actually with the connections on the tranny-sort of. The tach signal actually comes from the igniton coil. True it could be a malfunctioning tachometer, and you could actually read it off of the diagnostic module I believe it is IG, can't remember off hand

 

in my first reply i stated it was IG-

 

Whoops.....

 

excuse the ignorance, but would I need an sst to read it from the diagnostic module??

 

If you can borrow an oscilloscope, connect it to a trailing plug, you can measure rpm with it.

 

thanks for your info