Isuzu Repair: Idle problem, 1999 isuzu trooper, serpentine belt

Question
My wife has reported to me a few potential problems with her 1999 Isuzu Trooper. The car has fewer than 90K miles What could be the cause of a fluctuating idle on her Trooper? She reports that the RPM goes up and down,especially while warming up when the car is cold. The second problem is the TOD (torque on demand) lights on the dashboard for the rear stay on even when the button is not depressed/activated. She also states she smells a burning rubber smell. I can't seem to locate the origin of this smell. Is it perhaps related to the TOD malfunctioning? And finally (!), her Trooper always seems to use up 2-3 quarts (sometimes more) of oil between oil changes, either with conventional oil or synthetic. Is this normal? Thanks in advance

Answer
Hello James, check your intake gaskets for any leaks, also any vacuum lines unhooked, im sure you will find they are. Then Check your Timing belt and your serpentine belt/s for any faults/looseness, and third, Use lucas heavy duty oil stabilizer with castrol 10-40w oil, Make sure to clean out your throttle body and egr valve(DONT USE CARB CLEANER ON EGR VALVE!!!!!) The oil use is due to oil rings sticking on the piston and causing it to use oil. The oil stabilizer will help tremendously, also recommend Marvel Mystery oil as well in your gas and or oil in substitute to the lucas oil stabilizer, Let me know how this goes ok? MERRY XMAS!!!!!