mcleantmw

I continue to detect a slight coolant smell when driving with the heater on.........of course you kind of get used to it after a while but not healthy I'd guess. Last oil change at my MB Dealer they couldn't find any leaks. What needs to be done to further diagnose this issue?

Flash Gordon

Has the heater been replaced? Consider the age of your car, a new heater just may solve the problem.

cmriv

silicate build up in heater core/housing......


bet you your filter in your expansion tank is clogged full of silicate, unless you've replaced that before.