joe is correct! if the injectors are worn you could get a hot IDM to help the problem.
think of it this way- you have a electromagnet and you want to lift and object and it does it just fine at 110 volts, now place the object farther away an it can no longer lift it, then increase the voltage of the magnet to 140 volts then it will be able to magnatize the object at a larger gap!
now THAT I understand..