88 cherokee ignition module problems

[cdwazoo]

hellow i have a 88 cherokee 4.0 auto 180,000 miles. my problem started 5 months ago. it would not start one afternoon after being driven in the morning. did some quick checks..no spark. cheched connections and wires , all seemed ok. towed back to house. had almost 12v to module. checked wires again but wouldnt spark. next day it started right up.! had module checked at parts store and they said it was bad. got a used one. worked greaqt for 5 months. then no spark. this one checked bad too. ( if it sat for a day or two it would start..) got another used one and it lasted 5 days! my question is is there a problem with the wiring that could be burning the module up or did i just get 2 used modules with a little life left im em? i bought a new one,$130! but i dont want to install it until i investigate some more and get some other ideas. any help is appreciated thanks