Code result
P0177
Fuel Composition Sensor Circuit Range/Performance
Moderate severity
What it means
The flex-fuel composition sensor signal is within electrical limits but does not match expected values for the current fuel mix or rate-of-change is implausible.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Sensor drifted out of calibration
highOne of the most commonly reported causes for this code — check this first.
Fuel contaminated (water, dirt)
mediumA plausible cause — test and verify before replacing parts.
Related help
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