Ive been messing with this car a long time, my datalogger is always on.
I changed a couple things in my tune with tunercat, (which ive done many times) now all of a sudden my speedo doesnt read correctly in the datalogger. I did the speed calibration thing again which is pretty cut and dry no issues, the speedo is dead accurate but the datalogger is reading 10-15mph all the time, even when im going 100.. Ive used tunercat many many times and never had this problem, im thinkin its a bug since it never happened until i actually paid for the tunercat software. Please help me out, ive done the speed calibration 10x same ersult, how can the speedo be accurate adn the pcm not?

Ryan

 

Might want to add specific info about your car.... year, model, tranny type, etc.

Moving to "Computer Diagnostics & Programming"......