Returning for an update...a whole new can of worms has opened up. Seems at least some of the worms are escaping the can through the head gasket!!!! Did the MAF cleaner and the seafoam into the IACV. Drove up to the local ski resort and the car overheated bad. The main reason I am posting at this point is to keep people from spending unneccesary money. My advice is to look at the coolant reservoir before spending a dime on a 2.5. If it smells like exhaust or has a film, the head gasket is failing. If the car is rusty or high miles,it's not worth putting any money into it. I just spent close to $200 and wasted a bunch of time on coil,plugs,wires,knock sensor,seafoam,etc....Even though this engine is a basket case and on it's way out, I had the codes read again yesterday. I now have a vehicle speed sensor code. After some reading, I found out the IACV trouble code is likely being caused by a failing Vehicle speed sensor which causes the the computer to go into limp mode which causes a poor idle which causes the IACV code and also the knock which causes the knock sensor code. All this is a separate issue from the low coolant/ headgasket problem. So.... please check the VSS and the headgasket before you spend money on tune up parts. Also, I do not recommend pouring seafoam into the IACV or anywhere for that matter. Here is why: I poured less than 1/3 can into the air tube leading to the IACV and let it sit for 30 minutes. I then started the engine, which started rough but smoothed out quickly. I knew full well that even a small amount of liquid in the combustion chamber could cause a temporary hydrolock (this is why I only used about 1 1/2 oz.) On most engines this wouldn't be a problem, but if the head gasket is near failure (All the phase one 2.5's are) the increased pressure could blow it out big time. Not saying this caused the gasket to blow but it is definitely not helpful in this situation. Thanks for reading the long post and I hope It saves somebody some trouble.