P0177 - Fuel Composition Sensor Circuit Range/Performance

System Information

Some vehicles may run on a mixture of different fuels and the ECM will use a sensor to check that the mixture of the fuels is at the correct ratio

Fault Code Explained

The ECM has detected that the sensor output is incorrect due to an undefined reason. The sensor value will be within its normal operating parameters but is not reading or responding as expected for the current engine operating conditions.

Recommended Tests

It is recommended to follow the manufacturers recommended test plan when diagnosing this fault code