Heater stopped heating!

[Marcus]

Hello all,
I’m looking for advice.

On my 2007 ST v8, my heater stopped blowing hot air, or any temperature other than cold.
This happened about 6 months ago but fixed itself after a couple of weeks of me turning the dash temp dial back and forth. Then yesterday it lost all heat again.
I’ve searched this site and it sounds like a heater core might be the problem.

Please let me know if anyone has any recommendations.

Thanks.

 

[jonesin615]

is your in cabin temp for outside air reading correct? if not its your ambient air temp sensor prob, just sec ill pull up the service manual on it and see possible causes

 

[jonesin615]

Hello all,
I’m looking for advice.

On my 2007 ST v8, my heater stopped blowing hot air, or any temperature other than cold.
This happened about 6 months ago but fixed itself after a couple of weeks of me turning the dash temp dial back and forth. Then yesterday it lost all heat again.
I’ve searched this site and it sounds like a heater core might be the problem.

Please let me know if anyone has any recommendations.

Thanks.

hope this helps if need more lmk.

 

[Marcus]

Sweet.
Thanks!

 

[wsaunders212]

Sweet.
Thanks!

The temperature actuator is located under the left side of the console . This opens and closes the door from heat to cool , just put one on mine it’s not a difficult repair just takes a little time.

 

[Fuelishness]

Your problem has probably already been diagnosed. However, I have had this problem before and the core was stopped up. I disconnected the return hose to prove flow, of which there was very little. I then disconnected the supply side and used water pressure from a garden hose to back flush the core. It was effective and saved me from replacing the core. I then did a complete cooling system flush, with the heater supply and return blocked, replaced the low flowing radiator and refilled with new fluid. Problem solved.

 

[cadman777]

Your problem has probably already been diagnosed. However, I have had this problem before and the core was stopped up. I disconnected the return hose to prove flow, of which there was very little. I then disconnected the supply side and used water pressure from a garden hose to back flush the core. It was effective and saved me from replacing the core. I then did a complete cooling system flush, with the heater supply and return blocked, replaced the low flowing radiator and refilled with new fluid. Problem solved.

I had the same problem with my '04 XLT.
Plus, the AC evaporator was leaking inside the HVAC box.
So I removed it and replaced both.
BIG difference in both cooling and heating.
Another thing that typically goes bad is the connector to the blower motor corrodes.
The way to fix that is to buy a new connector + resistor.
Reason to replace the resistor is b/c the terminals are usually too corroded to fix (mostly rust that won't come off when scrubbed).