Misty Windows that donít clear, wet carpet, steam from dash vents, smell of antifreeze

12 January 2017  |  BigMick

Affecting: Anything watercooled with a heater

Coolant leakage happens when the heater-matrix (which carries hot water from the engine to warm the cabin) springs a leak due to corrosion or damage due to excess pressure. The first sign of this might be a wet carpet in the  foot well. Unfortunately it’s probably also one of the first components that gets placed in the car when constructing the interior, and typically means the removal of the dash-board in order to repair or replace. It’s a big job and shouldn’t be undertaken lightly, and it’s also important to find out why the matrix has deteriorated. A failing head-gasket leading to pressurization of the cooling system is a common reason (check for a leaking or flow restricted radiator in conjunction with this). The best action you can take against preventing this problem, is to ensure that you have your coolant changed every two years, and to ensure that the system is appropriately flushed each time.

Later vehicles with OAT (Organic Acid Technology) antifreeze which is typically pink, orange or red will often NOT have a recommended change interval included in the service schedule. This 'implies' that it is good for the life of the vehicle. This we disagree with strongly for a number of reasons. Guru Stu will outline our findings and recommendations in a future blog.