Sable V6-183 3.0L DOHC VIN S MFI (1997)
EGR Tube: Description and Operation
Orifice Tube Assembly
DESCRIPTION
The orifice tube assembly is a section of tubing connecting the exhaust system to the intake manifold.
PURPOSE
The assembly provides the flow path for the EGR to the intake manifold, and also contains the metering orifice and two pressure pick-up tubes.
FEATURES
The internally located orifice creates a measurable pressure drop across it 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 Powertrain Control Module (PCM).
