Passat L4-1984cc 2.0L DOHC (1991)
Fig. 35 Vacuum Hose Diagram, 16V (California)
The vacuum amplifier receives two vacuum inputs. The primary input is directly from the intake manifold and the secondary input is from the throttle
body (ported vacuum) before the throttle plates. The primary vacuum input is used to operate the EGR valve, while the secondary input is used as a
control reference. For examine, when the vacuum inputs are equal, such as during wide open throttle, the EGR valve will close, allowing peak engine
performance. The EGR valve should be open only during part throttle operation.
THERMO-VACUUM VALVE
