What it means
The control module detects an electrical fault in the turbocharger or supercharger inlet pressure sensor B circuit. The sensor’s location and the system’s configuration vary by vehicle.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Turbocharger inlet pressure sensor B measures pressure at the turbocharger or supercharger inlet, and the control module uses its signal to assess air entering the forced-induction system. P2374 sets when the electrical circuit for sensor B has a fault, such as an open signal, supply, or ground path.
Common causes
Most likely first.
- Open in sensor signal, supply or ground
- Connector corroded by underhood moisture
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
How to diagnose it
- Read freeze-frame data and live sensor B data alongside other intake-pressure readings to see whether the signal is absent or implausible.
- Locate sensor B using vehicle service information, then inspect its connector and nearby harness for moisture, corrosion, damage, or a loose fit.
- Check the sensor B signal, supply, and ground circuits for opens or poor connections using the wiring diagram and manufacturer's procedure.
- Inspect the sensor's pressure port or reference path for blockage, damage, or a disconnected hose where applicable.
- If the circuit and pressure path are intact, test sensor B against the manufacturer's procedure before replacing it.
Common fixes
- Reconnect and secure a loose sensor B connector.
- Clean moisture or corrosion from the connector and repair damaged terminals.
- Repair an open in sensor B's signal, supply, or ground wiring.
- Replace sensor B if it fails the manufacturer's test.
Can I keep driving?
With major power loss, smoke, or an intake hiss, avoid high-speed driving and heavy loads; stop if the engine runs poorly or smoke is heavy. Have it checked promptly because incorrect inlet-pressure data can affect engine control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.