Caps on motor oil bottles, pop bottles and beer bottles keep the liquid in. But a radiator cap is not any ordinary cap. Though it seals the cooling system from the outside, the radiator cap is ...

Symptom: An engine’s cooling system is overheating. The coolant level is low, but there are no visible leaks and no water in the engine crankcase to hint of water jacket or cylinder head problems.

According to Cameron, Tundras that overheat when driving at highway speeds may accidentally have bits of an old radiator cap inside the vehicle’s coolant system. The Toyota Tundra, based on Cameron’s ...