I have a jaguar xj8 whilst driving at low speed the car started to loose drive. Over 100 meters the car lost all drive and the engine was reving freely in gear with no acceloration. After stopping at the lights the car puled away the car jurked a surge of power and then lost drive again after white smoke came from the bel housing area.

When cool the car will give a small amount of drive for a meter or two in drive and reverse with the engine revving almost freely. . This power will then dissapear, the engine runs fine so I suspect its gear box or tourque converter related? Any ideas ..