Holes means leaks. How can the system build pressure if there is a leak? A better suspect is the radiator fan not turning on. The clue is the engine will not overheat when driving at highway speed because the natural air flow is sufficient to cool the radiator.
If the overheating occurs at every speed, have your mechanic perform a chemical test at the radiator for a leaking cylinder head gasket.
Wednesday, December 7th, 2016 AT 5:13 PM