Exhaust Gas RECIRCULATION (EGR) Orifice Tube Assembly
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The EGR orifice tube assembly is a section of tubing between the exhaust manifold and the EGR valve. The assembly provides the flow path for the EGR to the intake manifold and also contains the metering orifice and 2 pressure pick up tubes. The internal metering orifice creates a measurable pressure drop as the EGR valve opens and closes. This pressure differential across the orifice is picked up by the differential pressure feedback EGR sensor which provides feedback to the PCM.