Nox Sensor issues

stew

Member
Hi all. Our A2 FSI has put on the EML a couple of times recently, according to VAGCOM the fault is -

17443 - Sensor for Nox (G295): Signal Implausible P1035 - 35 - -

I'm assuming that this is the lambda sensor under the car?

Is there anything else this could be? The paperwork for the car shows a new one being fitted at a main dealer two years and 10k miles ago, I wouldn't have expected it to fail so soon.

The car has a few weeks warranty left, but the garage is 45 miles away so its a bit of hassle if its possibly a quick and easy fix.

Thanks in advance.
 
Hi stew Implausible signal could be a wiring issue - the wiring from the sensor enters the car via trunking under the car as the wire goes straight to the ECU in the passenger underfloor void. I would say it's worth going to the dealer and make a claim but insist on a genuine sensor as others are far from reliable. Also worth noting genuine sensors will have the wire as part of the sensor some generic ones require soldering in which is far from ideal. Good luck mike
 
Hi all. Our A2 FSI has put on the EML a couple of times recently, according to VAGCOM the fault is -

17443 - Sensor for Nox (G295): Signal Implausible P1035 - 35 - -

I'm assuming that this is the lambda sensor under the car?

Is there anything else this could be? The paperwork for the car shows a new one being fitted at a main dealer two years and 10k miles ago, I wouldn't have expected it to fail so soon.

The car has a few weeks warranty left, but the garage is 45 miles away so its a bit of hassle if its possibly a quick and easy fix.

Thanks in advance.

Hi,

the FSI's second (post CAT) sensor is a combined Lambda and NOx sensor. The NOx part monitors the output of the NOx storage CAT and regulates the running mode of the engine to switch between lean burn and normal running. That and the exhaust temperature sensor are vital part of the normal running of the engine.

As its more than just a basic Lambda sensor, its a very expensive and specialised part. If there is a warranty left I would get it changed. Last time I bought one it was £150, I expect its much more than that now.

regards

Andrew
 
I managed to get in back to the garage where I bought it this week as its just still under warranty. The issue was with the control module and they've replaced that.
 
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