What it means
The signal of the SAI air flow or pressure sensor is implausible during operation. The reading does not change as expected when the air pump is commanded.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The bank 1 SAI air-flow or pressure sensor measures the effect of air injected into the exhaust, typically during a cold start. P2432 sets when its signal is too low or fails to rise as expected when the control module commands the air pump, which can result from restricted passages or a sensor that no longer responds correctly.
Common causes
Most likely first.
- Clogged SAI passages
- SAI sensor drift
- Sensor element aged beyond calibration window
Symptoms
- Check-engine light on
- Rough cold start
- Reduced power or increased emissions
How to diagnose it
- Review freeze-frame data and graph the bank 1 SAI sensor signal while the pump is commanded to confirm that the reading stays low or fails to change.
- Inspect bank 1 SAI hoses, passages, and the check valve for blockage or sticking that could prevent airflow from reaching the sensor.
- Check the sensor connector and harness for chafing, corrosion, poor contact, or a signal circuit short to ground.
- Measure sensor power, ground, and signal response during a commanded pump test, using the manufacturer's specification for comparison.
- If the air path and circuit are intact, test the bank 1 sensor for drift or a failed sensing element.
Common fixes
- Clear a confirmed blockage from the bank 1 SAI passage or hose.
- Repair a sticking bank 1 SAI check valve if it restricts airflow.
- Repair a signal wire short, poor ground, or corroded connector.
- Replace the bank 1 SAI sensor if it fails its response test.
Can I keep driving?
You can usually drive gently if the engine runs normally, but expect increased cold-start emissions or rough running. Arrange repair soon, particularly if power is reduced or the warning is accompanied by other engine symptoms.
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.