Code result
P2178
System Too Rich Off Idle Bank 1
Moderate severity
What it means
Bank 1 fuel trim shows a strong rich correction during off-idle operation. The ECU is forced to subtract fuel to keep the mixture near stoichiometric.
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
Leaking fuel injector
highOne of the most commonly reported causes for this code — check this first.
Excessive fuel pressure
mediumA plausible cause — test and verify before replacing parts.
Stuck-open purge valve
mediumA plausible cause — test and verify before replacing parts.
Related help
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