hey so i have a 2006 Mazda 6s with the 3 litre bout 2 days ago i started experiencing over heating problems, no heat was coming out of my vents, and the car would only overheat when i would start driving, when i would shift into neutral the temp would start to drop slowly any idea on what this could be, gonna try burping the system, but has anyone had the same problem

 

Carry out a TK test ( checks for exhaust gases in coolant from a blown head gasket)

If thats good carry out the following,

Remove the thermostat, fluh the entire cooling system, fit a Genuine thermostat, vacuum fill the coolant. Run the engine with the radiator cap off until the cooling fans cut in, then fit a genuine radiator cap.

Go for a drive & fingers crossed its all good.