When this happens, the engine will sometimes not start, and when it does it runs at what seems like 100rpm and it cuts out, try again it will idle, go to accelerate, starts hesitating pretty badly. Put it in neutral, bring the revs up slowly, no problem. Open the throttle more than that, starts misfiring badly, seems to be misfiring on two or even three pistons, plugs and leads are recent, checked them and all ok. The next day, the car will drive like it was new, no dramas at all