I bought a 97 4.6L 4x4 EXT cab Windsor engine which was in pretty rough shape a few months ago. The current issue that I am working on is the heater. It acts like there isn't enough coolant in the system, as in, it gets hot when the engine is reved but blows cold while at idle.
When I bought the truck and was cleaning it out, I noticed an empty bottle of bars stop leak on the floor under the seat. So I am assuming that there was/is some leak somewhere in the system, though I can't really put my finger on where it might be. No noticeable leaks...
I flushed out the entire system using the add water and drain till it comes out clear method, then I used a prestone flush product, got that all out, and then I added this crap in an orange can that fixed the headgasket on my probe pretty well. let that dry out for a day and then flushed it again with water, and finally filled it back up with fresh prestone green, which I have heard many people on this site claim meets Ford's specs. The heater is still doing the same thing.
One thing I found odd in this whole process, is that not once has the temp gauge ever gotten more than half way up. When I have done this to other cars, it usually gets hot, like, almost overheating hot before I shut it off and let it cool, but the truck never got much above normal operating temp.
So, do you think there might be air in my system? if so how much does it cost to have it purged roughly? Should it be done at a dealer? or can any garage handle that? The main reason I am learning about cars is that I can't afford to pay someone else to do the work for me, but I suppose if it's something that I can't do, I'll just have to accept that.
What else could the heater problem be?
I have also noticed that the coolant is very foamy after driving it... is this normal?