As far as working on 22r's I really have no idea, I have a 3.0 and have not done a lot of work on the 22r. The answers I gave you are what I have learned from wrenching for over fifty years and they apply to just about all engines. Were is the coolant going, I have no idea, the same thing was happening on the 3.0 and I could not figure it out, no white smoke on start up but it was going somewhere. One day when I had it running in the shop I caught something out of the corner of my eye by the firewall so I looked over there, I saw a small drop of coolant forming on the heater control valve, and then it dripped. I looked underneath and there was no coolant on the floor so I let it run for about ten minutes and it dripped about three drops a minute. Then I remembered that the crossover pipe was right below it. The coolant was dripping on the pipe and evaporating. Put on a different valve and the problem went away. Only took me about six years to find it.