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P0234

P0234-TURBOCHARGER OVERBOOST CONDITION


WHEN MONITORED
While running.

SET CONDITION
The intake air pressure is above a calibrated value for a calibrated amount of time.

POSSIBLE CAUSES
- Other DTC's
- Wastegate stuck
- Turbocharger and/or wastegate damage
- Wastegate
- Turbocharger
- Wastegate control valve

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. OTHER DTC'S
With the scan tool, read DTCs.

Q: Do you have additional DTC's?

YES: Repair all other DTC's first. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Go To 2

2. TURBOCHARGER AND/OR WASTEGATE DAMAGE
Visually inspect the turbocharger assembly for signs of damage. Pay particular attention to the Wastegate area and linkage.

Q: Was any damage noticed?

YES: Repair or replace the Turbocharger or Wastegate. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Go To 3

3. WASTEGATE
Pressure the Intake air system per test INTAKE AIR SYSTEM PRESSURE TEST.
Pay particular attention to the Wastegate signal line and the Wastegate actuator canister area for leaks.

Q: Were any leaks detected?

YES: Repair as necessary. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Go To 4

4. TURBOCHARGER
Disconnect the wiring connector at the Wastegate Control Valve.
Remove the Wastegate Control Valve from the turbo.
Inspect the O-rings and the valve for damage.
Replace any damaged O-rings or a damaged valve.
Using a pressure/vacuum hand pump, apply vacuum to the tip of the Wastegate Control Valve.
Use your fingers to cover and seal the two radial holes located between the two small O-rings on the tip of the valve.
The valve should hold vacuum.

Q: Does the Wastegate Control Valve hold vacuum?

YES: Repair or replace the Turbocharger. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1
NO: Replace the Wastegate Control Valve. Perform the POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). Powertrain Verification Test - Ver 1