No heat

Thank you!
I don't know if a leak down test was done or not. The final result was the coolant in the radiator was bubbling at the end of the test. (Bleeding test was done )The rest of the tests, thermostat and heater core was okay. Test time was 1 hour.
The gauge on the dash board does not show overheating stays on the middle now, usually slightly less 1/8 inch. As being very cold few days 5 F I was turning the key halfway for 10 or 15 seconds stop, waited 15 -20 seconds then started the car to warm the coil.
Never seen the van overheating as mentioned above. During oil change (2,500 miles) all liquids inspected no problems. Do not hear any noise coming from the engine bit rough for few minutes at start being outside over night in cold.
Thank you !

Thank you.
Going to get a second opinion. Very good to know that the gauge will go up and down constantly! Thank you again.

Greetings,

Got 2nd opinion it is the blend door was told that the dash needs to be removed (2006 Pontiac Montana SV6) big job was directed to a rapid rad.
The van does not overheat, no smoke , as how much would cost to get an estimate?

Thank you !

Greetings,

Have read the related heater problems can't see if the dash needs to be removed?
Thank you!

Greetings Previously mentioned that first diagnosis was head gasket, The second time the blend door. Have postponed the blend door job. Today the van overheated stopped the van right away. Coolant in the reservoir suddenly got filled up small air bubble the size of a dime was coming from the hose one after the other into the reservoir. If the head gasket is really the problem wonder for a month had no overheating.
Thank you very much !

Thank you ! All I was told first time that has changed the coolant and done the bleeding raved the car for long time and said that the coolant bubbling. Left and for a month drove the van as was not overheating at all normal temp. Gauge. Second opinion is the blend door.. Have mentioned that in cold temperature before starting the van turned the key half way to warm the coil and waited 30 seconds before start. Does this effects anything?
Thank you again !

I don't know exactly the is called "coil" but was told If turning half way the key (but not starting the car) and wait until the.

Was told in cold weather turn the key half way till the guage on the dash goes up then stop turn back the key or take it out then wait 20 or 30 seconds. Then start the car. This way is warmed the engine instead a cold start. I understand is a "coil " that makes warmer.
Thank you !

Thank YOU ! So doing that can damage anything related to the engine?

Greetings Roy.

The van when is in idle is not over heating but soon as driving overheats. Seen another mechanic this is the third one saying that is head the gasket.
Thank you

Thank you !