My friend has an 88 635i with approximately 200K on the clock. The car has given him solid service thru the years. It idles like and champ and he has tested compression and all cylinders are in spec. But when he takes it out on the road and hits the accelerator the car just dies. I suggested the fuel filter or fuel regulator. It definitely sounds like a fuel issue to me but it is not my car so I was just giving an educated guess. Is this a common issue and what do you think it might be?