Heating problem

Hello,

I have a 2009 TRD Sport and frequently for the past month or so, when I turn on the heat I get cold air only. If I turn off the truck, then restart I get heat. Sometimes turning on and off once works, other times I need to turn on and off a few times before I get heat.
Any support would be greatly appreciated.

Steve

 

can you verify the truck reaches normal operating temperature even when you are not getting heat?

Any recent work done to the cooling system?

How many miles on the truck?

Any other problems regarding airflow, say changing between the heater/defrost outlets and the dash vents? Like sometimes it 'moves' and sometimes it doesn't?

Had anything in the dash apart recently, like radio work, custom wiring, etc?

 

The truck reaches normal operating temp without problem, 115k, and there has been no work done at all.
I have noticed that when the heat is working, the temp cools significantly when at idle but when underway, the heat works well.

 

Bump

 

I had something similar happen to another car, except it was more intermittent. Turned out to have some air bubbles in the heater core.
You could always try flushing the coolant system, perhaps there's something clogging the system.

 

And if you haven't already done so make sure the cooling system is full. Low coolant causes a lot of erratic heater operation issues.

 

Personally, I would do a drain, flush, new thermostat, followed by a bleed and see if that helps.

Howard