Originally Posted by __Ap2__s2k

Ok. This will be a rather lengthy post, but I need to give all the details so bare with me please. I've had over heating/air in coolant system plonked for like 2 months now. In the past 3 weeks I have replaced my thermostat (oem) intake manifold gasket and bottom radiator hose. After I installed these I bled the system following Billmans advice (always use his method). Maybe a week later the car over heats again and this time I break down and take the car to a reputable shop. The guy really knows what he's doing from all I know, and he's a good guy. Anyways, he discovers that my cap isn't holding pressure despite it having no visible signs of being faulty. So, replaced that, new coolant, bled the system, pressure tested the system and it didn't lose any pressure over something like a 5 hour period or so, he also tested for exhaust gases in the coolant as I was worried I may have a faulty head gasket. No exhaust gases in coolant. So, I'm happy, yay my car is fixed and it was all along a simple, inexpensive rad cap!.. Or so I believed. It's been a little over a week since I had this done and just a day or so ago, heat starts getting weak like it has before. It will only blow hot while I'm drive (60+) and blows cold as slow speeds or idle. I checked my bottom rad hose after letting the car warm up this morning and it was cold... Bingo! We have air in the lines I'm thinking. So the story now is. I'm not getting heat unless going fast, bottom hose is cold but my car is NOT over heating. Still should be air in the lines. My question is, how in the world am I getting air in my lines so slowly. It takes a week or more to accumulate these problems again. I'm so frustrated. There are no leaks or anything. Any advice is welcome since I'm at my ropes end with this problem. Sorry for the enormous post

Originally Posted by boyguan

A lot of our pumps do leak

Originally Posted by Billman250

I have never seen one, let alone a lot...I've been here a long time.

A lot is quite a stretch.