What causes the check engine light related to emissions to turn on in the Mercedes-Benz S-Class?

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What causes the check engine light related to emissions to turn on in the Mercedes-Benz S-Class?

The check engine light often illuminates due to emissions-related problems like faulty sensors O2, MAF, exhaust leaks, o r issues with the evaporative emissions control system. In Pakistan, poor fuel quality and dusty conditions can aggravate these faults.

Talha Kyanii asked on 11 Oct 2025 16:13:41 pm

1 Answer

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Gari Master - on 11 Oct 2025 16:14:46 pm

The check engine light related to emissions can be triggered by:

Faulty Sensors: Oxygen sensors, Mass Air Flow MAF sensors, o r other emission control sensors may fail o r give incorrect signals.

Exhaust Leaks: Leaks in the exhaust manifold o r pipes allow unfiltered gases to escape and disrupt sensor readings.

Evaporative Emission System Issues: Problems in the fuel vapor recovery system, like damaged charcoal canisters o r loose gas caps.

Poor Fuel Quality: Contaminants in fuel can affect combustion and sensor performance.

Engine Misfires o r Inefficiency: Incomplete combustion increases emissions and triggers warnings.

Prompt scanning with diagnostic tools identifies the exact cause for timely repair.