fireguyfire

Hi gents; I have a 2010 3500 with the smarty jr EGR and DPF delete. I have 270,000 km on the truck and it has performed flawlessly (and still does). I have been getting the codes P2262 (turbo boost) and P0471 (exhaust pressure sensor) lately and they come and go. The check engine light will come on and then go out a day later. I have cleared the codes a couple of times and it might be a week before they resurface.
I pulled the exhaust sensor, cleaning it, cleaned the orifice into the housing (which was restricted but not blocked) and insured I have good air flow through the pipe to the housing while running so I know that this is good unless the sensor has gone bad.
I am wondering if this is the famous sticking turbo vanes issue? Can anyone suggest the next phase of trouble shooting I should go through to fix this issue? Like I said earlier, the truck runs perfectly.
Would a bad exhaust pressure sensor throw both of these codes?

fireguyfire

Anyone have any suggestions? Sucks as my remote start won't work when the check engine light is on.

6.7L MegaCab

See attachment for schematic....

Theory of Operation

The Exhaust Gas Pressure Sensor is used to measure exhaust gas pressure in the exhaust manifold. The Powertrain Control Module (PCM) provides a 5-Volt supply to the Exhaust Gas Pressure Sensor on the sensor supply circuit. The PCM also provides a ground on the sensor return circuit. The Exhaust Gas Pressure Sensor provides a signal to the PCM on the Exhaust Gas Pressure Sensor Signal circuit. At key on, the readings for the exhaust gas pressure, intake manifold pressure, and ambient air pressure are compared. This fault code occurs if the exhaust gas pressure reading is different from the other two. During normal engine operation EGR position and Boost Pressure Sensor readings are used to calculate an estimated exhaust pressure. If the difference between the estimated and the value read from the Exhaust Gas Pressure Sensor is above a calibrated threshold for a calibrated period of time then an error is recorded. The key-on portion of the rationality will light the MIL immediately after the diagnostic runs and fails. The rationality portion has to fail in two consecutive drive cycles for the MIL to become illuminated. If this fault becomes active the PCM will light the MIL immediately. During this time the PCM uses an estimated exhaust gas pressure. The PCM turns off the MIL when the diagnostic runs and passes in four consecutive drive cycles.

•When Monitored:
Five seconds after key on.

•Set Condition:
The Exhaust Gas Pressure Sensor reading at key on differs by a calibrated amount of pressure from the Barometric Pressure Sensor and Boost Pressure Sensor or the Exhaust Gas Pressure Sensor reading varies from an estimated value during normal engine operation.

Possible Causes:
DEBRIS PLUGGING THE PRESSURE TUBE
DEBRIS PLUGGING THE PRESSURE SENSOR PORTS ON THE WATER OUTLET CONNECTION
EXHAUST GAS PRESSURE SENSOR

1.CHECK THE EXHAUST GAS PRESSURE SENSOR TUBE AND PRESSURE SENSING PORTS

1. Remove the steel tube between the Exhaust Manifold and the Exhaust Gas Pressure Sensor port (located on the water outlet connection).


NOTE: The orifice in the water outlet connection is 2 mm in diameter. Closely inspect this location as it can accumulate debris.


Is the pressure tube and pressure sensor ports located in the manifold and water outlet connection free from debris?

Yes

•Go To 2

No

•Clean the tube and pressure sensing ports.
•Go To 2



2.CHECK THE THERMOSTAT OUTLET

1. Remove the Exhaust Gas Pressure Sensor from the thermostat outlet.


NOTE: Carefully make sure the sensing end of the Exhaust Gas Pressure Sensor is clear. The Exhaust Gas Pressure Sensor diaphragm can be damaged if a tool is inserted into the end of the sensor. Take care not to damage the sensor.


Is the outlet and sensor free of debris?

Yes

•Go To 3

No

•Remove debris from outlet and wipe the sensor with a clean cloth. Reinstall pressure tube and sensor and retest.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).



3.CHECK THE AIR INLET/CHARGE AIR/EXHAUST GAS RECIRCULATION FOR LEAKS

1. Check vehicle/engine for leaks of inlet air (Air Filter to Turbocharger), Charge Air (Turbocharger to Intake Manifold), or EGR gases (Exhaust Manifold to Intake Manifold). (Refer to 29 - Non-DTC Diagnostics/Drivability - Diesel - Diagnosis and Testing) .


Were there any leaks detected?

Yes

•Repair leak condition.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No

•Go To 4



4.CHECK THE EXHAUST GAS PRESSURE SENSOR

1. Turn ignition switch on.

2. Wait five seconds after ignition switch is turned on.

3. With the scan tool, read DTCs.


Is P0471 stored?

Yes

•Go To 5

No

•Replace the Exhaust Gas Pressure Sensor in accordance with the service information.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).



5.CHECK THE EXHAUST GAS PRESSURE SENSOR OPERATION

1. With the scan tool, erase DTCs.

2. Start the engine and let it idle for one minute.

3. With the scan tool, monitor the Exhaust Gas Pressure Sensor reading.


Does the value fluctuate slightly, indicating the sensor is not stuck?

Yes

•Repair complete.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No

•Replace the Exhaust Gas Pressure Sensor.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L.

6.7L MegaCab

Theory of Operation

The Variable Geometry Turbocharger (VGT) is electronically activated by the Powertrain Turbo Actuator. The Turbo Actuator is a smart device and receives information via the J1939 BUS from the Powertrain Control Module (PCM). The Turbo Actuator performs its own diagnostics and reports failures back to the PCM using the J1939 BUS. The PCM then decodes the error message and converts it to a fault code. The PCM lights the MIL lamp immediately after the diagnostic runs and fails. The PCM will turn off the MIL lamp immediately after this diagnostic runs and passes in four consecutive drive cycles.

•When Monitored:
Continuously with ignition on.

•Set Condition:
The commanded position and the actual position do not match over a calibrated time.


Possible Causes
SOOT BUILD UP ON TURBOCHARGER
TURBOCHARGER

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


NOTE: If there are DTCs present with P2262, P226B, P226C, or P2563, address P2262, P226B, P226C, or P2563 before attempting to repair the other fault codes. If however, these DTCs are accompanied by DTC P0471, both DTCs should be addressed and repaired.


1.VEHICLE CONFIGURATION

1. The repair procedure is different depending on whether the vehicle is a Pick Up or Chassis Cab.


Is the vehicle a Pick Up or Chassis Cab?

Pick Up

•Go To 2

Chassis Cab

•Go To 4


2.OTHER DTCS PRESENT

1. Turn ignition on.

2. With the scan tool, read DTCs.


Are there any communication DTCs related to the J1939 Datalink present?

Yes

•Diagnose and repair the communication DTCs before proceeding.
•Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No

•Go To 3


3.TURBOCHARGER CLEANING

NOTE: Do not erase the DTC before attempting to run the VG Turbocharger Cleaning procedure. The procedure can only run if the P2262, P226B, P226C, or P2563 are present (active, pending or stored).


1. Reconnect the Turbo Actuator harness connector.

2. Turn ignition on.

3. With the scan tool, navigate to miscellaneous functions and initialize the VG Turbocharger Cleaning Procedure. Follow the directions on the scan tool completely.


NOTE: When the procedure is initialized you will see one of two messages on the screen.


Which message displayed on the tool?

Turbo does not need to be cleaned;

•The Turbocharger does not need cleaning, or cleaning of the Turbocharger will not fix the stick condition. If DTC P2262, P226B, P226C, or P2563 are active or pending, replace the Turbocharger assembly . If the DTC is stored, erase the DTC. Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L Procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

The engine must idle at 1,500 RPMS for 5 minutes prior to injecting the cleaner;

•The Turbocharger cleaning has initiated. Fasten the cleaning tool to the vehicle and follow the instructions on the screen completely. After the first attempt at cleaning is completed the test will run again automatically and determine if the Turbocharger has been cleaned. The scan tool can make up to three attempts to clean the Turbocharger before failing it. After the cleaning procedure has finished, the scan tool will display the results. If the scan tool displays VG Turbocharger cleaning was successful, the repair is complete. If the scan tool displays VG Turbocharger cleaning was unsuccessful, replace the Turbocharger assembly in accordance with the service information.
•Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L Procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


4.OTHER DTCS PRESENT

1. Turn ignition on.

2. With the scan tool, read DTCs.


Are there any communication DTCs related to the J1939 Datalink present?

Yes

•Diagnose and repair those DTCs before replacing the Turbocharger assembly.

No

•Replace the Turbocharger assembly in accordance with the service information.
•Perform the DIESEL AFTERTREATMENT VALIDATION - 6.7L Procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

Rollin'_Coal

If you're deleted and have spare wires hanging under the truck are they sealed up well? All my DPF wires are tied up to the frame but sometimes if they get real wet or muddy they will make some weird codes. Spray em off and seal up again and the issue goes away for a few months. Nothing ever comes of it, truck runs flawlessly.