My 1990 civic stalls after 10 minutes and then wont start for a couple of hours. Have replaced main relay and wires, plugs, ignition coil, but same
problem persists. I hear the three clicks have fuel but no spark. Any ideas

 

Get a junkyard distributor and see if that fixes it.

 

I had a similar problem on my 2000 Honda Civic SI, it turned out to be the main coil that was not giving a good enough spark to the plugs. I would recommend checking the distributor cap and rotor for oil, cracks, or a short ignition from the rotor.

Did you take out each spark plug and checked for the correct color of spark if any?

 

Will follow up and check spark and look to check the rotor and cap, thanks

 

Spark should be bluish white.

 

Get your icm tested. They can fail with heat.