Ok, today I just replaced my thermostat. I still dont have great heat. It seems like the coolant isnt circulating properly. I did replace the water pump last year. My car takes forever to heat up in the a.m. and still doesnt reach operating temperature. When I go on the highway the temp gauge drops right down. Also the thermostat I took out today was functioning properly. I tested it in a pot of boiling water. What else should I do or look at? Do I have a blockage somewhere? Im completely at a loss.

 

Try draining your clean coolant and backflushing the system to dislodge anything. If it's not too much trouble, maybe take the thermostat out and let its orifice flow with fresh clean water. It's also not entirely unheard of for thermostats off the shelf to be defective. Just sayin...Are you sure you properly bled the system? Is it overheating?

 

I think I properly bled the system. I let the car run with the heat all the way on. I did this for a couple cycles. I did notice on the way to work this morning that the temp gauge did go over half way. So, it is running hotter than it has before. Could this be air stuck in the system? What the best way to back flush the system? Do you think its my water pump again?

 

Oh, my friend, I do not envy you this situation. A lot of us have been there. Take a look at my thread on this very topic.

Bottom line, if your certain that your t-stat and water pump are good...you either have a plugged heater core, air pockets in the cooling system, or both.

 

Did you make sure the new thermo was good when you replaced it? Just because it's new doesn't mean it works.

 

Heater problems also. I lost heat all of a sudden. Thought the heater core was blocked. I pulled all the pipes off and flushed the pipes. The water flows around fine. Still no heat. The water pump looks ok but the only thing it can be now is the pump simply is not pumping correctly. I can bleed the top heater pipe then a few mins later the pipe will be empty of water. Can sometimes get a little heat but not for long.

Check your pump. Take off the pipes going into the heater. Start the car and see if it pumps water out. If not then guess you have similar issue to me.

Anyone else seem similar issues?

 

I've always avoided this problem of air in the system by filling the expansion tank to max then starting the car with the cap off and let it run 5-7 minutes with the cap off topping off as necessary. Then shut er' down and let it cool for 15-20 minutes and usually it'll take a little more coolant. Start it again and let it run with the cap off for 3-4 more minutes then make sure its at the max line and cap it. Never had a trapped air problem, even after completely draining the block. On the otherhand, as me and someone else stated, just because that thermostat is new, doesn't necessarily mean its functional.

 

You sound like you have a B6 and not a B5. On the B5, the intake and output hoses into the heater core are side-by-side. Even if he's getting circulation out of the output hose, that doesn't mean that his heater core is not plugged. When I had this problem, I had a little bit of output from the heater core, but nothing like it was after my mechanic flushed it out and used compressed air on it to get all the crud out.