APPLICATION: Replaces CUMMINS Tool Number 3164001. Works on Cummins ISX, Cummins Signature Engines. MATERIAL: Quality aluminium Test Adapter Plate and Flexible Tygon tube (Diesel Resistant). FUNCTION: This test checks for combustion gas leaks back through the injector rail check valve or other conditions that will allow gas leakage through the injector into the fuel rail. SAVE MONEY: Use this tool to check the Fuel Injector before replacing injectors or metering actuators. BENEFITS: .