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WASTEGATE/Boost Pressure Test

NOTE: Either road test or shop test may be used to check wastegate operation on 3.8L engines. It is not necessary to perform both tests.
  1. Inspect wastegate and actuator assembly for linkage damage. Check condition of hose from throttle body to wastegate solenoid and from wastegate solenoid to actuator, then remove hose.
  2. Connect a hand operated Vacuum/Pressure Pump (J-23738) in series with component Gauge (J-28474) to actuator assembly hose.
  3. On 2.0L engines, 4 psi (.28 kg/cm2 ) pressure applied to actuator should move rod .015" (.38 mm). On 3.8L engines, 13.5 psi (.95 kg/cm2 ) pressure applied to actuator should move rod .015" (.38 mm). Replace actuator if not operating properly. Check new unit and crimp threads on rod to maintain proper calibration.
  4. Remove test equipment. Reconnect actuator-to-wastegate solenoid hose.