P2374
Turbocharger Inlet Pressure Sensor B Circuit
The pressure sensor at the inlet of the second turbocharger (B) - on twin-turbo or sequential-turbo systems - is reporting a circuit fault. The ECU cannot determine inlet pressure and falls back to a substitute value, which limits boost control accuracy on this stage.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Common causes
Ordered by how often each turns out to be the cause.
- Open in sensor signal, supply or groundCommon
- Connector corroded by underhood moisturePossible
Parts involved
- Turbo Inlet Pressure Sensor B
- Turbocharger B
P2374 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.