DCS

Sequoia'd mentions that you may as well change the knock sensor while you're that far in.

This is a huge job. It makes sense to eliminate every other possible cause before embarking on a search for a blockage. If your heater blows good hot air, and your temp gauge hovers near the middle, it's possible that the temperature sensor that relays info to the ECM is bad. The temp gauge sender is not the same sensor that the ECM uses to gauge engine temperature.

Also, if you do start searching for a blockage, check all the easier hose connections and passages before you dive into the plenum.

Good luck! Keep us posted.

Brenjen

Hitting that ultra steep incline to burp mine helped a whole lot. It still has a slight trickle sound of air in the heater core but nothing like what it was before. If you're having the problem try it.

Also, I'm sure all of you are aware that you should have your over flow bottle filled between the full & low lines as well. If not then it will just suck air back into the system. I just thought I'd mention the obvious, sometimes people forget about that.

Sequoia'd

Yes... as a matter of fact, while you are pouring the AF in, watch this line with the rubber hose removed. When AF starts to come out, it is full and you are done!

I agree with other posters... always check the easy things first and don't overlook the obvious. You will be miles ahead if you don't have to dig deep into the top end to find a clog.

BTW, as stated before, same EXACT symptoms, heater blew hot air (would set your feet on fire) and I also replaced the sensor... here's a hint... first sensor on the left along the bank of sensors at the rear of the engine closest to the firewall, when you pull the sensor out, see if any coolant is on the sensor. Check carefully, if no coolant, it's probably blocked passage as coolant can't get to the sensor. Hope this helps!