Fuel and air

P0097 — Intake Air Temperature Sensor 2 Circuit Low (Bank 1)

Severity: low Safe to drive

What P0097 means

The engine control unit reads the voltage from intake air temperature (IAT) sensor 2. The sensor is a thermistor: its resistance and signal voltage drop as the air gets hotter. P0097 sets when the voltage is lower than expected, which the ECU reads as unrealistically hot air. The usual culprits are a failed sensor or a signal wire shorted to ground.

Symptoms

  • Check Engine light on
  • Worse fuel economy
  • Rough idle
  • Hesitation or surging when accelerating
  • Reduced engine power
  • Possible hard starting when cold

Possible causes

  1. Failed intake air temperature sensor 2
  2. Damaged or corroded wiring or connector
  3. Signal wire shorted to ground
  4. Problem with the 5 V reference or sensor ground
  5. Rarely, a faulty ECU

How to diagnose

  1. Scan for codes and save the freeze frame data.
  2. Compare IAT 2 reading with actual air temperature on a cold engine.
  3. Inspect the sensor connector and harness for corrosion, chafing, oil or moisture.
  4. Unplug the sensor: if the reading goes to the cold extreme or the code changes to a high-input code, the sensor is likely bad.
  5. Measure sensor resistance and compare it to the spec at a known temperature.
  6. Check for 5 V reference and a good ground at the connector with a multimeter.
  7. Test the signal wire for a short to ground with both ends disconnected.
  8. If the wiring and sensor are fine, suspect the ECU.

Common fixes

  • Replace intake air temperature sensor 2
  • Repair damaged wiring or replace the connector
  • Fix a poor ground or reference circuit
  • Reflash or replace the ECU (rare)

Questions and answers

What does P0097 mean?

It means low voltage in the circuit of intake air temperature sensor 2 on bank 1. The ECU sees a signal that looks like very hot air and treats it as implausible.

Can I drive with P0097?

Usually yes, for short trips. Fuel economy and performance will likely suffer, so get it diagnosed soon.

How do I fix P0097?

Check the connector and wiring first, then the sensor itself. Most often the fix is a new sensor or a repaired wire, followed by clearing the code.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.