I was leaning in DodgeVan’s direction as well… I believe he is onto something with the ignitor assy… and in the same thought process…I would be suspicious of the coil and the engines COMPRESSION as well.
You need to do a few tests for us Gearheads… When the car is COLD…and you know it will start… Open the hood and remove all 4 Spark Plugs… Plug one or more spark plugs into a wire and ground it to the block for a spark check. Have someone turn the engine over for you while you ground out a plug…or rig up a starter bump switch and turn engine over w ignition ON…and the fuel injection or fuel pump fuse/relay REMOVED…
TAKE NOTE OF THE SPARK… Is it Nice and Strong? Perhaps a nice FAT BLUE SPARKY ? If so this is GOOD…Blue is good and strong…Yellowing toward a WEAK spark quality.
Then install your plugs and go driving until you know that she will not start again if you tried… REPEAT the Spark Test…and tell us what you GOTS… If you notice a PALE YELLOW/WEAK spark…then you are onto what we are trying to tell you… If its yellow…and weak…You either have a failing ignitor…or ignition coil I believe… Perhaps your distributor is all self contained on that car…coil and ignitor assy all in one distributor… Im not certain…you tell us.
ANOTHER thing it could be is a bit more serious…and will involve a COMPRESSION check while COLD…and another when you know that she doesn’t want to start while engine is HOT
*** OOOPS WAIT !!! DUH…IN FACT what the hell ? Do the Compression check WHILE you are DOING the COLD and then HOT Spark quality test !!! Get two things done at the same time actually…YES…DO THIS… APOLOGIES
You will have all the plugs out and it will be the PERFECT time for said compression check anyway… Write down the comp test numbers COLD…and Again…when No Start HOT… Note the spark quality. For your cars Sake I am hoping you notice a drastic difference in the SPARK quality department… This is by far the LESSER of the two evils here. The answers to these questions will get us to a solution I believe.
Let us know… I bet we solve the problem if you do exactly what I outlined here for you…