If your radiator cap fails to hold any pressure your boiling point will be that of water 212 degrees. So yes it can cause an overheat but usually in low speed operation. Radiator cap is cheap from aftermarket so just replace it and see if that cures your problem. you could have a bad thermostat, a hose collapsing during operation, restricted flow of coolant or even air flow through the radiator itself.
Search Chevrolet Captiva Sport Questions
Chevrolet Captiva Sport Experts
Related Models For Sale