I have a MT-82 so using clutch not brake but same principle. Not sitting in front of my car but when you start your car the msd control box should have green led and then when you press the break the led should turn off signaling activation (or vice versa, can't remember but I can check if you want). If that works then the other thing to check is to see if you have the plugs for left bank and right bank reversed. The car will run if they are reversed (runs with a miss). I always turn my advance trac / traction control completely off when I use the 2-step. Only other thing I can think of is too make sure you have a good ground and the 2-step is set low to like 2,200 RPMs incase you have the settings reversed (8,200 rpm instead of 2,800 rpms as an example).
Yah, red and green led - couldn't remember lol. Take a look at my pic, left and right banks use the same interchangeable type plugs (different wires). Mine are buried in the loom so I can't tell you if red is left or right bank.
