Intermittent starting problem

I have a 1994 Dodge Caravan manual 5-speed. The minivan would start fine in the morning, but after I drive it to the store, park there for approximately 20 minutes, the minivan would oftentimes won’t start; it would make a clicking sound, but the engine would not turn over. Only after several attempts, the engine would start. I’ve taken it to my mechanic, and he’s replaced the starter twice. I’ve replaced the battery. My mechanic never seem to be able to reproduce the problem as the van would start fine for him. I’ve asked him to check out the starter, alternator, and battery, and they all check out fine. In desperation, I took it to the Dodge dealer, thinking that they would be the mechanic of last resort. One day later, they, too, couldn’t find the problem. They claim that they test drove it, and still the van started fine for them. I don’t know if the mechanic had rested the car for the required 20 - 30 minutes.



Any idea as to what could be wrong? Thank you in advance for any advice.

Check BOTH ends of both battery cables, and all grounds, including any ground wire/strap between the body and the engine. Also check the starter relay and its connections. LAstly, it could be the ignition switch.