Q: Stalling,bad fuel mileage,won't start without Acceleration, rough idling.

This may be related to a couple of different things. I would recommend checking the idle air control valve/module which works similar to the MAF sensor in that it regulates air intake as it is mixed with fuel prior to being injected into the motor. When this is not working correctly this will cause an imbalanced air/fuel mixture causing the motor to stall or idle rough. I would also check the catalytic converter to make sure it is not clogged as this could cause poor fuel mileage as well as poor running conditions. I would suggest having an expert from YourMechanic come to your home to perform a thorough diagnosis of your land rover, and make necessary repairs.