Tach Signal Jumpy on stim

[lem0nmonkey]

i have a MS1 V3 board, running VR input, setup for the gm 60-2 wheel, using a Jimstim setup for the same, using a 12v pull up, now i get signal, and megatune sees rpm;s as i turn the pot, but they jump up and down buy about 2000 rpm, could this be caused by the setup in megatune or do i need to run the tach input inverted?

also i find when i turn the jimstim on i loose my touchpad on the lap top, i can use a usb mouse fine but the touchpad stops working, is this to do wth the comport the ecu connects through? i have a usb adapter board fitted to the ecu, not using the serial connection?

[bmbelo]

Hi there. Had the same issue initially. Make sure your no. cylinders and ignition options (60-2 wheel) are up to par with your DIPs on the JimStim. Hope it helps.