An exhaust leak near the front sensor. A vacuum leak or a dirty MAF sensor. An aging or contaminated front sensor (often an air-fuel ratio sensor). Low fuel pressure.

Trouble codes › P2195

P2195 O2 Sensor Signal Biased/Stuck Lean (Bank 1 Sensor 1)

Q: What does P2195 mean?

P2195 means bank 1's front oxygen sensor reads lean when it shouldn't, from a leak, a dirty MAF or an aging sensor. The engine computer checks the front oxygen sensor against the rear one. P2195 means the front sensor reads lean when the engine shouldn't be: either the sensor is biased or there's a real lean problem (often unmeasured air).

Oxygen sensors

P2195 means bank 1's front oxygen sensor reads lean when it shouldn't, from a leak, a dirty MAF or an aging sensor.

The engine computer checks the front oxygen sensor against the rear one. P2195 means the front sensor reads lean when the engine shouldn't be: either the sensor is biased or there's a real lean problem (often unmeasured air).

Can I keep driving? Yes, but get it fixed soon.

Usually drivable, but get it checked soon; a lean engine can misfire.

Common causes

An exhaust leak near the front sensor
A vacuum leak or a dirty MAF sensor
An aging or contaminated front sensor (often an air-fuel ratio sensor)
Low fuel pressure

Symptoms

Check-engine light
Hesitation, sometimes lean codes

Common on: Toyota Camry, Toyota Corolla, Toyota Highlander

What to check first

Check fuel trims and for P0171.
Look for exhaust leaks ahead of the sensor and vacuum leaks.
Clean the MAF sensor.
Replace the front sensor if no leak is found and it stays biased.

What does P2195 mean on your vehicle?

The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.

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Related codes

General guidance for P2195 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.