P0169: Incorrect Fuel Composition
What to do
If the vehicle was recently refuelled somewhere unfamiliar, mention it. Otherwise expect the sensor or fuel quality to be investigated.
What this code means
The fuel composition sensor is reporting a blend the module cannot work with. Flexible-fuel vehicles measure ethanol content so fuelling can be adapted between petrol and high-ethanol blends, and a reading outside the expected range either means genuinely unusual fuel or a sensor that has drifted. Water contamination in the tank produces the same conclusion.
Likely causes
Start here
- Faulty fuel composition sensor · moderate
- Fuel contamination · specialist
Less common
- Water in fuel tank · moderate
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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