Is a faulty oxygen o r mass air flow MAF sensor causing increased emissions o r rough running?

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Is a faulty oxygen o r mass air flow MAF sensor causing increased emissions o r rough running?

Recently my Land Rover has had rough idling, hesitation, o r decreased mileage, and I suspect an issue with the air‑fuel mixture. Could problems with the oxygen O₂ sensor o r MAF sensor be causing my vehicle to run “rich” o r “lean,” leading to higher emissions and triggering fault lights? How can I test o r confirm these sensor issues before replacing them?

Talha Kyanii asked on 11 Dec 2025 13:22:32 pm

1 Answer

16 views |

Gari Master - on 11 Dec 2025 13:23:32 pm

Yes, both sensors play a key role in the air-fuel mixture and emissions:

O₂ sensor issues: If the sensor fails, the ECU cannot adjust fuel properly, leading to rich o r lean fuel mixtures. This causes rough idling, hesitation, higher emissions, and lower fuel economy.

MAF sensor issues: A dirty o r faulty MAF sensor sends wrong airflow data, making the ECU deliver incorrect fuel, resulting in stumbling, black smoke, and emission light triggers.

Diagnosis & Solution:

Use an OBD-II scanner to check sensor codes like P0101 for MAF o r P0130-P0167 for O₂ sensors.

Visually inspect and clean the MAF sensor with special cleaner never use regular sprays.

Replace faulty sensors if cleaning doesn’t help.