i know i asked how many volts the o2 sensor is.. i just realized i said o2 sensor.. when really i meant rpm signal wire.. is a 0 to 5 volt system?

thanx
James (the dumbass)

The actual tach signal is measured in mV. Use a multimeter on the tach wire.. solid white, no stripe, maybe brown/pink/tannish dots... it might go as far as 5V at 7000+ RPM, but i couldn't tell you..

yeah.. it should go up in volts dependignn on high the rpm

Quote
yeah.. it should go up in volts dependignn on high the rpm

Of course it does. I just don't remember the scale of it. I remmeber it was reading in millivolts, but scale that to 7,000RPm, i don't know. If you have a stutterbox, i imagine it would be pretty easy to find out }(

Last I checked the tach wire was not a linear 0-5V signal (like the TPS or MAP). It was a pulse type signal that could not be properly read by a volt-meter. The signal switches from low to high at a certain frequency. I believe that the frequency increases as you increase the RPM. I believe that you would need an oscilloscope to properly read the tach signal.

Corbin

'95 ESI-T
HRC+FMIC+ETC...



Gimme fuel...Gimme fire...Gimme that which I desire

^^^ Correct. The signal isn't linear and almost every manufacturer uses a different method to trigger the tach. My WBo2 logs the rpm signal and lots of people have to change a resistor (I think) to get it to work. That is in addition to the hi/lo jumper setting that's available.

True and True ^

Quote
^^^ Correct. The signal isn't linear and almost every manufacturer uses a different method to trigger the tach. My WBo2 logs the rpm signal and lots of people have to change a resistor (I think) to get it to work. That is in addition to the hi/lo jumper setting that's available.

thats the same software / hardware i want to use. im going to build the unit this weekend. did you have to put a resistor in or did you just hook it up and it worked?

thanx
James

I didn't build mine, and it was plug n play.