I have a 93 civic ex that will not start when the motor is warm. It will crank fine when the engine is cold. For example: If I drive for 30+ mins and stop for gas, I have to wait approximately 10-15 mins before the motor will start again. The motor will turn over, but not actually start. I can smell fuel and can hear the humm from the fuel pump when the key is first turned on. It's like its not getting fire, but I can't figure out why not. I know that I need a new idle air control, being as the engine surges when in N/P. I'm new to Hondas and am at a loss. Thanks.

 

When it won't start, pull one of the spark plug wires and put a spare plug in it and check for spark.

The main relay is the most common cause of this. It causes a lack of fuel though. Still, everyone with the affected models (88-95) should resolder their main relay as a preventative measure.