Originally Posted by glc
Replace the distributor cap and rotor.
If that doesn't work, your wires could be suspect if their older, also an older PIP sensor (Stator) An error code scan may divulge that, along w/ other possibilities, like an out of range MAP/or TPS. But start w/ the most likely. All of these potential causes require a certain dewpoint to be reached. Any heat reduces that to restore function, but at a reduced level, and it will eventually get worse till whatever component involved, fails completely. Sometimes observing the engine compartment in the dark wihile attempting a start will show something. You can sometimes duplicate the condition w/ a water spray must bottle, especially the plug wires or a cracked distributor cap.