i have a ppp airshifter its been working great but now wont shift allthe wiring is the same as its been,plenty of air.the selinoid has 2 black wires comming out ,what do i hook them to to test the noid?

Connect one to ground and the other to 12v. It doesn't matter which wire goes to which.

Sean

thanks,noid works ill try a different chip.

got it fixed,the msd selector doesnt work on the rpm i shift at all the other selections are fine.guess ill have to use a single chip or get a new select box.