Hi, My heat works, but it is not real hot...I set it at 86 it is comfortable but really should be hotter I think...Also if I shut the car off leaving the heater settings untouched and come back and restart the car the rear defroster turns on with the heat but not all of the time...

 

Is the engine running at the correct temp also what is the outside temp when the rear defroster comes on

 

Check coolant temp, feel upper rad hose, check thermostat and finally check aux cooling pump is operating.

With system at 86 degrees your heat output at vents should be at least 120 - 130 degrees if all is working well...

Possible heater core is partially blocked...

 

Thanks guys...I will investigate above items...Rear defrost comes on in the 30s I think but not all the time...

 

What temp is shown on the outside temp gauge

 

It was 41 yesterday...Had the heat off and the rear defrost came on again when I returned to car and started it...Probably an electrical glitch I will have to live with...