When it doesn't start it usually tries to turn over, but doesn't. We then let it "rest" for about 5-10 minutes and most of the time it will start right up. If we haven't waited long enough then we have to go through the process again. Saturday we were stuck at the grocery story for probably a half-hour because I just kept waiting longer and long to try to start it and on the 4th or 5th try it finally started.
If the coil isn't too expensive, I'd replace it too. Coils, when they're getting weak, are extremely heat-sensitive. If they don't fail completely, they work better cold than hot.
That is, if the starting problems happen shortly after it's been running.
If it typically starts fine first thing in the morning, but gets harder to start after it's been running, that's a symptom that could (but doesn't necessarily) point out the coil as a culprit.
The heat factor could also tie in to oil-soaked plug wires.
