When your Duramax begins throwing a P2563 code, a scan tool will read ‘Turbocharger Vane Control Position Sensor Performance‘. The vane position sensor controls the unison ring and turbo vanes located within the Duramax’s Garrett turbocharger. P2563 and P003A are common engine codes amongst 2004.5 to 2016 Duramax turbo engines which us variable geometry Garrett turbochargers. While not covered in my post, this tends to be a most common problem for LLY Duramax’s compared to later years.
What does the Vane Control Position Sensor do?
The inside of a VGT (variable geometry) turbo has what is called a unison ring. The unison ring sits around the compressor wheel, and has “vanes” on it, which look and almost function like pinball bumpers. While traditional fixed-geometry turbo’s also have these rings, they are fixed in one direction. VGT turbo vanes are able to adjust their positioning which controls airflow and ultimately controls turbine pressure ratios.
The turbo has a VGT solenoid, which is hydraulically actuated, that controls the vane position and movement. The vane position sensor relays a signal to the ECM which then sends a signal to the VGT actuator telling it what position the vanes should be in. When this sensor fails, the ECM provides incorrect signals to the solenoid, which creates turbo issues and therefore performance issues.
What Causes Duramax Vane Position Sensor Failure?
While the P2563 and P003A codes are most directly linked to the vane position sensor, it’s not always the problem. Additionally, the turbo vanes can stick from being dirty or gunked up with carbon and diesel particulates. When the vanes stick, you will likely get the P003A code instead of P2563. However, the sensor itself can naturally go bad over time, or just be partially faulty due to dirt and gunk.
- Stuck turbo vanes due to dirt & gunk
- Completely failed vane position sensor (natural wear and tear)
- Dirty sensor and wiring
- Unison ring gets stuck to turbo housing
- Internal turbo components rusting
While the sensor does go bad from time to time, it is very common for these codes to be thrown due to the turbo itself. Internal components can rust and get stuck over time, and the sensor itself can get dirty and stop functioning properly.
P2563 & P003A Symptoms
- Check engine light (with said codes, obviously)
- Sluggish performance, acceleration, etc.
- Boost levels below target
The most common diagnosis is through the engine codes. While you will notice some sluggish performance, it may not be very noticeable if you are easy on the gas.
As previously mentioned, a good portion of the time the sensor is not actually bad. It is commonly caused by the internal components of the turbo getting dirty, or the sensor itself getting gunked up. With that being said, a lot of folks will first try to pull the sensor and the VGT solenoid and clean both along with the wiring. Part of the reasoning here is that the sensor is about $500 alone. If this fails, cleaning the turbo itself is a good second step.
Here is a good order of operations for diagnosing and repairing the P2563 and P003A codes:
- Pull the vane sensor and clean it along with the wiring (requires this special removal tool)
- Pull the turbocharger and clean the internal components like the unison ring
- Run scan tests and VGT Learn tests to determine what is at fault
- Replace the sensor or the turbo (depending on which is at fault)
If you do both of these with no luck, you have two options: replace the vane position sensor, or replace the turbo. Considering the associated costs you will likely want to use a Tech 2 scan tool or do a “VGT Learn” to determine if the issue is the sensor or if the issue is the unison ring. If you have a bad unison ring, you can usually clean it and get away with proper turbo functioning for 20,000 or maybe 30,000 miles, but the turbo will eventually fail and need to be replaced.
Given the cost of pulling the turbocharger, if you are not DIY’ing the replacement, I’d recommend replacing the full turbo otherwise you’re going to end up spending another $1,500 in labor to have the turbo pulled and replaced.
Garret Replacement Sensor
The Genuine GM sensor costs like $600+ and is a common failure point, so I recommend avoiding spending the much on something that will likely fail again over time. The best alternative is getting one from Garrett Turbos for about half the cost. You can get two of these for the same price as one genuine one and two will way outlast one factory one.