Code result
P21F5
Fuel Control System B Too Rich Off Idle
Moderate severity
What it means
Fuel Control System B Too Rich Off Idle (Bank 1): the fuel-trim control is correcting for an over-rich mixture in this operating range.
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
Port injectors leaking
highOne of the most commonly reported causes for this code — check this first.
Fuel pressure high
mediumA plausible cause — test and verify before replacing parts.
Related help
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