Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › 2005 Honda Element – mystery air in engine cooling system › Reply To: 2005 Honda Element – mystery air in engine cooling system February 17, 2020 at 8:19 pm #916734 WilfParticipant I replaced the radiator, hoses, and radiator cap. Also inspected thermostat and looks new and works perfectly (hot water test).