Check engine light on: Codes, Causes & Fixes
A steady check engine light means the engine computer has stored a fault that affects emissions or engine management. In most cases you can keep driving normally for now, but have the code read soon – many auto parts stores and any OBD-II scanner can do this. If the light came on right after refueling, check that the gas cap is tight; loose caps are a classic trigger for EVAP codes.
558Codes
2.7Average severity
12%High or critical
18%DIY-friendly
Severity distribution
Most viewed
P0135
Powertrain
The heater inside the upstream oxygen sensor on bank 1 isn't working or its circuit is faulty.
Low
P0174
Powertrain
The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction…
Moderate
P0300
Powertrain
The engine computer sees misfires that jump between cylinders or hit several cylinders at once.
High
P0420
Powertrain
The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly.
Low
P0430
Powertrain
The bank 2 converter on a V6, V8 or split-exhaust engine isn't cleaning the exhaust well enough.
Low
P0101
Powertrain
The MAF sensor's airflow reading doesn't match what the engine computer expects…
Low