Code result
P019B
O2 Sensor Delayed Response - Lean to Rich Bank 1 Sensor 3
Moderate severity
What it means
Bank 1 sensor 3 O2 sensor reacts only after delay during lean-to-rich transitions. 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
Sensor aged
highOne of the most commonly reported causes for this code — check this first.
Related help
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