just curious if datalogging will show me my tach/rpm, at least show me what the ecm sees

or does it see that info at all?

 

Yes you will see RPM and Vehicle speed.

print screen from when Im logging my Camaro
(not a big picture, but as you see, you get alot of info, like spark adv. /knocking / if you running rich/lean. exakt BLM, injector Volts and pulsewidth. Commanded rpm and the real rpm (commanded is what the ecm wants, and the real rpm can be a little different) IA temp. Engine temp. EGR duty cycle. o2 volts. and so on.. so you get alot of info about your car.

 

great thanks, whats the difference between command and real rpm and is both in the ecm or is one what my dash displays?

 

The commanded rpm is what the ECM wants the engine to idle/run at.
But as we all now, the ECM wants a perfect value, and it the real world that isnt possible, so if the ECM commands the "engine" to rpm at 750rpm maybe it will idle at 725rpm (in real time and that is what you see at the gauge)

 

This is me using WinALDL, you can see all of the sensor values, RPM, speed, etc:
http://youtube.com/watch?v=hm_Y6_CFDPE

 

WinALDL also works with our cars
but it uses 160BAUD and is mich slower then 8192BAUD wich could send many streams very fast .

BTW, Ward, did you see the PMs I sent you ?