same old problem with a 89 cherokee
 

ok buddy blew up the old 4.0 so he bought a used one and it was running like a champ before it was pulled . well guess what NO SPARK i know like u guys wanted another post about this . we have changed the coil the cps and the ign mod ( the part the coil sits in ) we have 12v on the yellow wire on the 3 wire connector in to the mod and while cranking we have 5v-5.8 v on the yellow wire on the 2 wire connector. i tested the cps and it is with in range but everything i have read is its a 3 wire well this one is a 2 wire red and black only no 3rd wire now somewhere along the lines someone cut the connector off of both side of this and i cant seem to find the diagram that states the color of the wire i need to hook to i want to make sure that the red wire is hooked to the right wire and so on i have a long list of things to test tomarrow and while testfireing after checking stuff i noticed that the factory tach wasnt moving while cranking at all not even a flutter any ideas? i know that the engine much be at 300rpms bufore things happen but is the no rms on the tach a problem to look in to ? any help would be great as we would like to have this running for the rock climbing in gilbertmn this comming weekend