Wastegate: Testing and Inspection

1. Inspect actuator linkage for damage.
2. Check tubing from compressor housing to actuator assembly. Replace if necessary.
3. Remove compressor housing to actuator assembly hose, then attach vacuum-pressure pump J-23738, in series with compound gauge J-28474, to actuator assembly.
4. On 1984-85 models, apply 7.5 - 8 psi pressure to actuator assembly. The actuator rod should move .015 inch. On except 1984-85 models, apply 13.5 psi pressure to actuator assembly. The actuator rod should move .015 inch. On all models, if the actuator did not respond properly, it should be replaced. Prior to installing actuator, test as outlined above, then crimp threads on actuator rod to maintain calibration.
5. Remove vacuum-pressure pump and reinstall hose.

Road Test

1. Tee compound gauge J-28474 into tubing between compressor housing and boost gauge or MAP sensor switch with a sufficient length of hose to place the gauge in the passenger compartment. Ensure gauge and hose are in good condition to prevent possible leakage of air/fuel mixture.
2. Disconnect and plug wastegate solenoid hose.
3. On all models with conditions and speed limits permitting, perform a zero to 40-50 mph, wide open throttle acceleration and maintain speed for two to three seconds. Boost pressure should reach 8 to 9 psi on 1984-85 models, or 13 to 14 psi on except 1986-87 models.
4. If boost is not satisfactory, replace actuator assembly. Prior to installation, test actuator as outlined in step 4 of Wastegate-Boost Pressure Test.