hi guys, ive got a 96 , p 38, 2.5 bmw engine, some times a little hard to start, when cold, and a bit of smoke, got one of them hot fix kits fitted, but now the big bmw mises a beat sometimes, just for a second or too, driveing along fine, then seams to stop, for a second, then runs another while, if anyone has any ideas, or fixs , please