Thank you Kim and Ron for your replies, It is a 5 wire wideband sensor, I googled for some information about wideband sensors and this is a bit more complicated than I thought. I will do some more research on wideband sensors. First I am going to change the oil and filter, because I read there are s...

Hello everybody, My Kia Sportage (2011) with 2.0 CVVT engine has a little dip in performance, so I decided to take a look at it. Fuel trims look OK and I captured the pre and post lambda sensor with picoscope. My questions: The pre lambda has a value between 2 and 2.5 Volt, is this normal? I never s...

Hi all,

It has been a while, but my problem is solved.
I replaced the Cat for a brand new one and the MIL stays off.
Thank you for all of your replies!

Over and out!

Hi All,

Today I did a road test as suggested.
Temperature at the post cat sensor is above 600 degrees and sensor values are included in the attachment.
The red line indicates the pre cat sensor and green the post cat sensor.
To me it looks like the sensors are responding just fine.

Thank you for replying Ron and Victor,

It is very usefull and educational, I will do a cruise road test in a couple of days.
I Wish you all a happy new year!

I have looked at the fuel trims and I think it looks OK, but the long term fuel trim at partial load is 3.5% and the short term fuel trim is pending between -8% and 0%. It that acceptable?

I've included a screenshot in te attachment.

Hi Ron,

Thanks for your reply, the capture was at 2500 rpm (steady). I did not look at the fuel trims, I will check it.

To be continued...

Hello everybody, Can you help me with a problem on my VW Polo? The MIL is on and after diagnosis with VCDS (VAGCOM) it appears to be a problem with the catalyst (P0420) "Efficiency Below Treshold" I also captured the output from pre- and post lambda sensor and it seems to me that the catalyst is ind...