no spark 1986 Cabriolet

It's either the ECU or a bad ignition control module. I have read other forums and the same symptoms you are having were exactly like the individual with a bad ECU. Here is what he had to say: When I purchased my Cabriolet it had this same problem of a single spark then nothing. I replaced all the rest of the ignition system before I found the problem, but I had to replace the ECU (the big electronic box on the drivers side back under the hood in its own separate compartment) It was an easy fix and can be done by anybody with basic tools. Im not saying this is your problem Im just saying I had the symptoms you described and it fixed it for me. If you want to try to do it locate a new or used ECU then: 1. Disconnect the battery 2. Disconnect the ground strap on the ECU bracket 3. Remove the screw holding the ECU bracket on and take the ECU and bracket out 4. Unplug the ECU and remove it from the bracket 5. Plug the replacement ECU in and attach it to the bracket 6. Re-install the bracket 7. Re-attach the ground strap 8. Reconnect the battery Its that easy. I hope it works.