No bro it is not OK to consume oil even on cng. Inspect the plugs one by one & may be you could easily figure out which cylinders are weaker & consuming oil.
Bro either it is ff or non-ff, both versions consume some patrol but the quantity you have mentioned is way too high than normal. Get your car's throttle body serviced first from a reliable person. May be this alone would solve both high rpm & high patrol consunption problem. If the problem persists, then you might need to get the patrol injectors & cng emulator checked.
Sent from my SGH-I757M using PW Forums mobile app