I was able to fix this problem last week. I removed the intake plenum and throttle body and clean them, replaced the PCV valve, cleaned and applied copper gasket to the gaskets and cleaned the mass air flow sensor. After I got it running I threw in a can of Seafoam. Everything seems fine and dandy now.

New problem. It has been getting pretty cold here, in the negatives. IÆve jumped into the Montero, once or twice, and cannot for the life of me shift from 2-high to 4-high until the engine has warmed up. IÆm guessing I need to swap the tranny fluid. Any recommendations when I do this? Additives that are good for extremely cold weather?