Hi jbonneterre, Thank you for replying. The car works great and doesn't heat up, but my heater will blow cold air when I stop at a right light on the way to work. As long at the car is moving the air is nice and warm. Is the thermostat the issue? Regards.IMO as long as you dont have issues with coolant temperature or heater it should be allright. mine works perfectly and i dont plan to change it. I did a rebuild last year on another 3.5 and the original one was mint condition, i reused it.
However it is not an expensive part and if you do a coolant flush you could.
If you have a 3.5, know that it is not that easy to reach (i have big arms and hands).
Hi jbonneterre, Thanks again for the reply and link to that item. Have a great day.That looks like air in the system. I would try to bleed it, you might have air that gets stuck in the heater core at idle.
You might also hear some bubbling noise after reving the engine.
I am not trying to sell anything but this would make the job really easy:
Amazon.com: Lisle 24680 Spill-Free Funnel: Automotive