Yesterday I discover that the cabin heater is not working. It blows cold air only. The air condition is working just fine and the engine temperature is normal
My first thought was the thermostat was malfunctioning and prevented coolant to flow through the cabin heater. I removed the thermostat but the heater still blows cold air
I have discover yellow foam in the expansion tank, which is not good. I believe it may be due to mixing of different types of coolant, or it may be rust and dirt, due to the coolant cleaner I added. I used the red long life type coolant. I've drained the system and I now in the cleaning witch tapwater prosess. I am planning to flush and drain once more before refilling long life coolant. Unfortunately I don't believe this will solve the problem
Is there any way to check if the coolant is flowing through the cabin heather?
Is there any way to prevent air-pockets?
At last I planning to look at the heater electrical system. I don't not much about it, except for checking fuses.
Any good advices on how to fix it?