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Boost Pressure

  1. Disconnect wastegate duty solenoid connector. Engine must be at normal operating temperature. Disconnect line from wastegate valve controller. Using a "T" fitting, connect an air pressure gauge. Use enough line so that gauge may be carried inside passenger compartment.
  2. Boost pressure should be checked at 2400 RPM with a wide open throttle. Normal pressure is 7.2-8.3 psi (2.4-2.8 kg/cm2 ). Reconnect wastegate duty solenoid.
  3. If boost pressure is too high, check the rubber hose that connects the intake manifold to the wastegate valve. Replace if defective. If wastegate valve is not operating and remains closed, replace the turbocharger. If boost pressure is too low, replace the turbocharger.