No heater

[Nomadnev]

My heater on my colarado is only blowing cold car not overheating and water level is fine
Any ideas
Cheers Nev

 

[RichC4]

Could be the valve which allows water into the heater matrix is broken or has become disconnected. It's at the top back of the engine in the middle on the firewall - check to see that the cable moves the valve as you would expect.
Alternatively your heater matrix could be blocked.

You can also end up with no heat if the water level is slightly low - this happened to me, the engine ran fine but the cabin wouldn't heat - the matrix is the highest point I think so most likely to show a lack of coolant.