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EGR Valve

EGR Valve:




The EGR valve is a stepper motor design. A stepper motor (6) drives a worm gear, that is in mesh with a spring (1) loaded plunger (5). The valve (2) end of the plunger (4) controls the flow of exhaust gases (3). The plunger movement is controlled by the Powertrain Control Module (PCM). By turning the stepper motor in different directions, the PCM controls the opening of the exhaust gas passage to the intake manifold.