Hello- My 2008 Range Rover Sport is idles fine at 1000 RPMs when I first start it. While in park I turn on the air conditioner and the RPMs fluctuate between 200 and 700 and it continues to fluctuate when I turn the air conditioner off. Just for some back ground, I have recently replaced the mass air flow sensor, the air filter, the battery, the spark plugs, and added a can of BG 44k. The car runs better now that it has in a long time except when idling in park or at stop signs. It recently died at a street light in the middle of the intersection. Does anyone have any suggestions to fix this? Thanks!