Turbocharger Boost Control Position Sensor Range/Performance Problem
The turbocharger boost control position sensor is out of range or experiencing a performance issue.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
Inside the system, the turbocharger has a position sensor that reports where the wastegate is. If the computer sees a value that's lower or higher than expected, it sets this code. This could mean the turbo isn't boosting properly, which can happen if the wastegate is stuck or the sensor is faulty.
What the computer is actually seeing
The engine control module (ECM) expects the turbocharger boost control position sensor to send a signal that reflects the actual position of the wastegate. If this signal is out of the expected range, usually below 0.5 volts or above 4.5 volts on a 5-volt reference, the code is set.
What a healthy reading looks like
Signal from the turbocharger position sensor should be between 0.5V and 4.5V within normal operation; otherwise, it triggers a fault.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the vehicle's wiring harness and connector for the turbocharger position sensor. Look for damage or corrosion.
- 22. Verify the boost control position sensor's voltage output. It should be between 0.5V and 4.5V at idle with the key on, engine off.
- 33. If the voltage is out of range, replace the sensor and retest. If within range, proceed to the next step.
- 44. Inspect the wastegate for proper operation. Manually move the wastegate actuator to ensure it is not stuck.
- 55. If the wastegate is functional, check for leaks in the intake and exhaust system that could affect boost pressure. Repair leaks as necessary.
Common causes
- Faulty turbocharger boost control position sensor
- Stuck or faulty wastegate
- Wiring issue or bad connection to the sensor
- Turbocharger malfunction or damage
- Exhaust leaks affecting turbo operation
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with code P0029?
It's drivable but you may experience reduced power and efficiency. Address the issue soon.
Will the code come back after repairs?
If repairs are done correctly, the code should not return if the root cause is fixed.
Why does P0029 sometimes happen with P0299?
Both codes can relate to turbocharger performance issues, so if there's a malfunction in the turbo system, both may trigger.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →