Check Engine Light Due to Emissions Sensor Faults

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Check Engine Light Due to Emissions Sensor Faults

Some Proton X70 owners in Pakistan have reported the check engine light CEL illuminating with emission-related fault codes, often linked to sensors like the oxygen O₂ sensor, mass air flow MAF sensor, o r EVAP system. What are the typical causes of these emission-sensor warnings on the X70, what do the common diagnostic trouble codes DTCs indicate, and how should owners address these warnings safely?

Talha Kyanii asked on 19 Dec 2025 12:08:49 pm

1 Answer

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Gari Master - on 19 Dec 2025 12:12:22 pm

When the check engine light CEL illuminates on the Proton X70 and is traced back to emissions-related fault codes, it’s often due to issues with sensors that monitor the engine’s air-fuel mixture and exhaust emissions. Key components like the oxygen O₂ sensor and mass air flow MAF sensor play a big role in regulating combustion for proper emission control. If an oxygen sensor fails o r sends incorrect data, the engine control unit ECU may adjust the air-fuel mix improperly, triggering a CEL and potentially causing rough running o r higher fuel consumption. A simple diagnostic scan with an OBD-II tool will identify the specific trouble code so the faulty sensor can be repaired o r replaced.
Gari.PK

What to do:

Scan the car with a diagnostic tool to read the error codes.

Fix o r replace the faulty sensor indicated by the code.

Regular maintenance of intake and exhaust sensors helps prevent false readings.