93 was begining not to start on occasion, replaced the cap and rotor, radiator and hoses, ran fine back to house, then next day car ran for 20 miles on highway, parked came out after an hour would not turn over, change the main relay module still not luck. any wisdom, pleae reply, sounds like I am going to need to take it to the shop!!!!

 

When your car does not start, check for spark. If you have spark, check if your fuel pump is running. If its not running, check the main relay again. If the fuel pump is running, you don't have fuel pressure for some reason. The problem could be that a bad check valve or a bad fuel pressure regulator is not holding residual fuel pressure so all the fuel in the lines is turning into vapor as soon as the fuel pump shuts off. The injectors cannot spray vapor. Once the engine and fuel cools down, the fuel turns back into liquid and it works again. If you want to know how to check if the check valve/FPR is not working, ask. The more common problem with civics is that the main relays overheat.