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My sons 2003 VW Polo 9N 1.4 keeps throwing up OBD Code P0140 02 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)

I keep cancelling it but after a couple of weeks it comes back so will need to change it as MOT coming up soon.

Where about is this sensor located on his engine as it is hard to see where it is!
also there are several different types for his car which one do I need to get and from where?

I am not fussed about using a secondhand one as he will be selling the car soon anyway, so if anyone has one please let me know.

That Lambda sensor is on the exhaust, maybe as far back as under the front doors, the place where its cable plug/socket is in inside a plastic box about the same point, so if I remember correctly, you remove a plastic nut and it can then be opened to unplug the end of the sensor cable.

The S1 B1 sensor is way up at the mani-cat (manifold and cat in one unit), so you will not get confused with it.

Get onto the NGK website and find out which model it is, you might need to look under the same aged SEAT Ibiza unless they have changed things over the passed 10 years!

Buying a used one or an almost like the real one, does not seem to work often with these items on these cars, so you could end up paying for a retest or loosing a sale if you take the cheap way round this - feeling lucky?

Thanks for the info.
So rather than have a garage do it is it quite an easy job for a confident diyer?

Oh yes, that sensor is a lot easier to reach than the one in the manucat! Maybe try removing it when the engine/exhaust is hot.

Just had a look and its going to take time to remove all the plastic panels to get access in such a confined space.
Easy job if you've got a ramp!

I've ordered the part a Haas Lambda Sensor New only £27.48 from Halfords!

http://www.halfords.com/webapp/wcs/stor ... _710441151

Guess I'll just have to pay a garage to fit it!

I've only ever removed these plastic covers to clean the muck out from under them, so that means that when I looked at this, it looked like it could be done without touching these long covers, did you see the cable coming across from the exhaust to a plastic box/cover thing?

Edit:- I hope that you have done your homework or let Halfords pick the right one as I've just looked at that link and it does not mention pre-cat of post-cat options and for which engine variant it is for.

Brand:FAE
Housing Colour:Black
Length [mm]:650
Number of ports:4
Type:DIRECT FIT
Fitted Quantity: 1
Exhaust System After catalyst; Lambda Sensor Diagnostic Probe; Transmission Type Manual Transmission

I typed in the Reg and it says it's for that car.

Well that is more info than I could get that site to reveal, I found out that all the NGK ones were engine specific, but nothing was offered on that one when I inputted a Polo 1.4 16V 2003 - I tried to check using my wife's previous Polo 1.4 16V 75PS 2002/2003 but as it was a personal import new, its UK reg was invalid as it was on most databases!

Yes it's weird sometimes it comes up and sometimes not!

Well was there a good ending to this repair?

Being replaced on the 6th September.