"92 sable starting issues

My '92 has major starting issues. about once a week, it'll crank, sputter then die. After that it'll take about 20 mins. to recatch. today it wouldnt start at all after that. i recently changed the plugs and distributor,had a diagnostic done on it and no problems,illedgedly. that worked for a while, now back to the same crap. This has been going on for about 7 months.Its a 3.8L. Any suggestions please.............

Check and clean all connections to ignition module on distributer. Loose,dirty connections may have vibrated apart after the first fix. Check to see if spark is coming out of the coil wire 1/4 inch from a ground. If no spark, the coil wire may be defective. If wire is good, you may have a bad ignition control module or coil could be defective.

PS: New/rebuilt distributers may or may not come with a quality ignition module.