LBZ - P2563 (Turbocharger Bost Control Position Sensor Performance, VGT)"

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The code is referencing the solenoid which controls how much boost the turbo charger is supposed to make for optimal performance of your engine. If this code is present, make sure and confirm that your MAP & BARO sensors are reading correctly. With Key on engine off (KOEO) this sensor data should read the same (or very similar) to what the BARO is reading. If not, then you should identify which of the sensors is your problem. The reason it’s important to verify these sensors are reading correctly is this: the MAP sensor identifies how much boost your turbo is making by taking the difference in pressure between the BARO reading and the MAP reading. The reason we need the BARO reading is that atmospheric pressure is different everywhere. If the BARO is reading 14PSI and the map is reading 22PSI then you have 8PSI of boost in your system.


Here is how to identify if your turbocharger position sensor is operating properly:

1- Run engine until operating temperature is reached.

2- Check resistance on turbocharger vale position control, it

should range from 3-7 ohms

3- Perform a turbo learn test with a scan tool

4- If this issue is still occurring after the learn test, monitor the

vane position while commanding boost with your scan tool

As you being to command boost, verify that the actual

position of the vane is matching the commanded

If the actual position is fluctuating more than 5%

before stabilizing, check for good oil pressure in the


If good oil pressure is present, remove the solenoid

and check for debris and sludge.

If all looks good, then replace the turbocharger

solenoid. Attempt to command the position solenoid to 100%. If it stops at a certain value over multiple tests, a bad unison may to be blame and turbocharger replacement may be necessary.