Sounds like a stuck injector. My friend had his '79 Rabbit diesel do this and it really sounded like the motor had grenaded!! We rebuilt his injector with a new nozzle kit and all was well. Try not to run it too long with the bad injector as it is putting alot of fuel to the cylinder. Do the one line at a time process to find it.

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My Truck.. 2007 DODGE, 5.9 Cummins, 6spd stick, 4X4. My car..1977 240D, OTHER WHEELS...1955 VW Oval window bug, European Delivery (Holland) with a 1700cc, 2 barrel, Porsche drum brakes. 1939 WILLYS Pick-up. 1967 Triumph 200cc Tiger Cub. 1976 Honda 550F 4cyl Motor Cycle.