Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

The owner told me that on many occasion, after about 20 - 25min into the driving, he got CEL but never manged to read the code using the paper clip method.

By now, I fired up the engine many times and even test driven the car but never had to keep running the engine for such long period and thus, no CEL.


However, while warming up for the compression check, the CEL triggered.

Read the code and it was #41, The Front O2 sensor heater circuit.

I already knew that someone modified the OEM Eng loom to extend the O2 sensor cable for the aftermarket header.

There was also a strange looking non-WPC as part of the extension cable.

After discussing with the owner, decision was made to replace the Front O2 sensor, replace the extension cable and put proper WPC back on the OEM Eng loom.















The photo speaks by itself.

Surprised that it manged to pass MOT.












Another really seized O2 sensor.

Normally, it's the rear one that struggles but due to the design of this aftermarket header, even the front one has seized.

Although I bought 2 sensors and matching extension cables, we decided to leave the rear bank for now.

Much easier dealing with it when the Eng/Gbox out of the bay.