Code result
P2177
System Too Lean Off Idle Bank 1
Moderate severity
What it means
Fuel trim values on bank 1 indicate a lean condition during off-idle operation. The ECU has to add significant fuel correction to maintain stoichiometric mixture above idle.
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
Vacuum leak under load
highOne of the most commonly reported causes for this code — check this first.
Low fuel pressure / weak pump
mediumA plausible cause — test and verify before replacing parts.
Contaminated MAF sensor
mediumA plausible cause — test and verify before replacing parts.
Related help
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