01 P0013 B Camshaft Position - Actuator Circuit (Bank 1) • 02 Warning Light On Dashboard That Could Indicate Imminent Eng… • 03 Tom Cruise Is Back Behind The Wheel: Days Of Thunder 2 Anno… • 04 P0016 - Crankshaft Position Camshaft Position Correlation B… • 05 How Long Should You Wait Before Changing Your Car’s Oil Aft… • 06 U0020 Low Speed CAN Communication Bus Performance • 07 P0075, P0076, and P0077: Intake valve control solenoid circ… • 08 Crank Angle in Engines: Everything You Need to Know • 09 P0300: Random or Multiple Cylinder Misfire Detected – Cause… • 10 U0021, U0022, U0023, U0024, U0025 and U0026: Low Speed CAN … •

DTC codes / Volkswagen codes / P1106

P1106 · VolkswagenOxygen Sensor Circuit Bank 2 Sensor 1 Voltage Too Low/Air Leak

P1106 on Volkswagen vehicles indicates that the engine control module (ECM) has detected a voltage signal from the bank 2 sensor 1 oxygen sensor that is lower than expected, which often points to an air leak or a faulty sensor circuit. The ECM monitors the sensor's output and sets this code when the voltage stays below a calibrated threshold for a set period, indicating a lean condition or a wiring problem.

SystemPowertrain
Code typeVolkswagen specific
SeverityMedium
Fix difficultyIntermediate
AreaFuel and air metering

Symptoms you may notice

  • Illumination of the check engine light, often with no other noticeable symptoms
  • Rough idle or hesitation during acceleration
  • Reduced fuel economy due to the engine running lean
  • Occasional misfire or stumbling, especially when cold
  • A faint hissing or whistling sound from the engine bay if a vacuum leak is present
  • Failed emissions test due to high nitrogen oxide (NOx) levels

Common causes, most likely first

  1. Vacuum leak or unmetered air entering the intake system after the mass airflow sensor
  2. Faulty bank 2 sensor 1 oxygen sensor (slow response or contaminated)
  3. Damaged or corroded wiring or connector at the oxygen sensor
  4. Exhaust leak before the oxygen sensor, allowing outside air to be drawn in
  5. Leaking intake manifold gasket or cracked intake hose
  6. Faulty positive crankcase ventilation (PCV) valve or hose
  7. Low fuel pressure or clogged fuel injectors causing a lean condition

How to diagnose and fix it

  1. Perform a visual inspection of all intake and vacuum hoses for cracks, loose clamps, or disconnected lines
  2. Use a scan tool to check live data for bank 2 sensor 1 voltage and compare with bank 1 sensor 1 to identify inconsistencies
  3. Smoke test the intake system to pinpoint any vacuum or air leaks
  4. Check the oxygen sensor wiring and connector for damage, corrosion, or loose pins
  5. Test the oxygen sensor heater circuit and signal voltage with a multimeter to verify sensor operation
  6. Replace the bank 2 sensor 1 oxygen sensor if it is slow or unresponsive
  7. Verify fuel pressure and inspect fuel injectors if no air leaks are found

Common Oversights in P1106 Diagnosis

  • A loose or cracked oil filler cap or dipstick can create a vacuum leak that triggers this code, so always check these simple items first.
  • The bank 2 sensor 1 oxygen sensor on Volkswagen engines is often located in a difficult-to-reach spot, and a faulty sensor may still produce a plausible voltage signal, so live data analysis is crucial.
  • Exhaust leaks upstream of the oxygen sensor can cause a low voltage reading because outside air is drawn into the exhaust stream, mimicking a lean condition.
  • A failing mass airflow sensor can cause a lean condition that affects both banks, but P1106 specifically points to bank 2, so comparing bank-to-bank fuel trims is essential.
  • After repairs, the ECM may need to relearn the oxygen sensor adaptations, so clearing the code and performing a drive cycle is necessary to confirm the fix.

Can I keep driving with P1106?

It is generally safe to drive with P1106 for a short period, but avoid aggressive acceleration or heavy loads because a persistent lean condition can lead to elevated combustion temperatures and potential engine damage. Have the fault diagnosed promptly to prevent worsening performance and emissions.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for Volkswagen vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage