Code result
P2414
O2 Sensor Exhaust Sample Error Bank 1 Sensor 1
Moderate severity
What it means
Same as P237A but on the upstream sensor B1S1 (pre-catalyst). A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
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
Sensing element fouled
highOne of the most commonly reported causes for this code — check this first.
Related help
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