The box on the inj. pump is hooked up to a control box that is usually located inside the car behind the right side kick panel. It has something to do with the control rod in the injection pump. Bosch used the same thing on Cummins 12 valve diesels in the Dodge trucks with the inline pump.

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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.