Engine running rich - High CO and HC emissions.

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GAZZEH
Donor 2024
Posts: 9
Joined: 17 Dec 2021, 09:15
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Engine running rich - High CO and HC emissions.

Post by GAZZEH »

Dear all,
Please help if you can
Thanks in advance for your valuable input.
C4 - 1.6 VTi 16v 120 (B7) - Engine EP6C - 4-speed automatic gearbox
Model year 2012 – 111,700 km
Failed periodic inspection for High emissions (CO reading: 3.5% and HC reading: 400 PPM)
Scan tool (Klavkarr 210) returned the following code P0030-21: Heated oxygen Sensor (HO2S) Heater Control – Circuit Malfunction (Bank 1 Sensor 1)
Replaced O2 sensors Upstream (Bosch LS 17217 - 0 258 017 217) and Downstream (Bosch 0 258 986 6032 with universal connector) and used Winny’s DPF & GPF On-Car Cleaner to clean the catalytic converter.
CO emissions dropped to 2.7% (Which is still abnormal and extremely high)
Scan tool (Klavkarr 210) returned the following code P0030-1F: Heated oxygen Sensor (HO2S) Heater Control – Circuit Malfunction (Bank 1 Sensor 1)

Please notice that the code number is different, but the description is the same.

New O2 sensors readings under different driving conditions (attached as a png file):
Upstream still reading rich even when the foot was off the gas pedal and the fuel was cut off?
Downstream is always in an open loop and reads lean (in columns 4 and 5), while upstream is still reading rich?
Attachments
New O2 sensors readings under different driving conditions
New O2 sensors readings under different driving conditions