I decided to use the Sea Foam I have had since I got back in February and at 1/4 tank put a can in and did the PCV Suck. After the initial 1/2 can inhale and subsequent engine stall I let it sit for 30 minutes, than sucked the rest of the can. I had positioned my truck at the back of the garage, tail pipe out the patio door (can you tell I waited until my Wife was gone?) I turned it on and revved a huge cloud out the tail pipe and let it idle and went inside for breakfast after about ten minutes I came back and the smoke was gone but I realised I had left the AC on also and it was now blowing hot. DAMN! I checked the entire system, agonized, searched the forum for ideas, looked at the FSM, kicked myself for breaking it and generally allowed my day to be ruined. I just went to the store, after it sat for several hours and it works! Does the system have some kind of a safety that shuts down if it senses possible harm being done to it? Man am I glad. I have a 1400 mile Laredo trip coming up and have done it once sans AC in my BMW and can say without fear of contradiction it sucks driving in the heat long distances without AC!