Distributor gets power from ignition coil. Replacement suggested. Had the same problem......I work at the USPS...we have lots of this issue!!!!I've determined the ECM is not receiving a distributor reference pulse from the newly installed Caldone distributor. Had replaced it because I thought that was the problem, of course it came with new pick up coil and module. After replacing the distributor the engine started right up but shut down 4 hrs later and would not restart. Does anybody have any tips for checking the four wire harness leading from distributor to ECM other than just a continuity check?