Code result
P0173
Fuel Trim Malfunction
Moderate severity
What it means
Fuel trims on bank 2 exceed adaptation limits in either lean or rich direction. The ECU cannot maintain stoichiometric mixture within calibrated boundaries.
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
Oxygen sensor bank 2 aged
highOne of the most commonly reported causes for this code — check this first.
Vacuum leak bank 2 side
mediumA plausible cause — test and verify before replacing parts.
Related help
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