New Car

M

MariaE

New Member
Hi All
I'm new to the owners club. I have had my A2 SE for 3 years and love it to bits. It's getting a bit tatty.... my bad driving him indoors says..... so I have decided to change to an A2 sport a year newer but in much better condition.
Hubby is busy getting it through the MOT and is having a problem with the oxygen sensors. He has changed both and cleared the fault, then started it to take it to the garage for it's MOT, but the light has come back on the dash..... any info much appreciated!
 
Air leaks can cause lambda (O2) faults, however its entirely possible the emissions are fine, when was the car registered?
 
Locate your nearest A2OC Free Scan VCDS member.
Get it scanned, and go from there.

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Mac.
 
As already mentioned it is best practice to fit genuine lambdas however they no doubt come at a cost!!
A smoke detector may be needed?
 
Years ago a 2004 1.4 petrol polo which was low mileage used to throw the eml for 02 sensor faults had two genuine ones fitted but every 6 months used to put eml light on but the emissions were absolutely spot on instantly, never found the route of the problem sadly. If its an early car it wont fail for the light alone thou
 
Howey said:
Years ago a 2004 1.4 petrol polo which was low mileage used to throw the eml for 02 sensor faults had two genuine ones fitted but every 6 months used to put eml light on but the emissions were absolutely spot on instantly, never found the route of the problem sadly. If its an early car it wont fail for the light alone thou
Click to expand...
 
All of the items the car failed the MOT on which to be honest were not a lot for an old car have been rectified its just this Damned light
All of the emissions were spot on thou
 
MariaE said:
He didnt use genuine sensors but he did get them from a reputable parts company
Click to expand...

I think the originals are NGK I know from experience that there are differences and eurocarparts for example sell o2 sensors that aren’t correct for this engine


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When was the car first used/registered, prior to 1st july 2003 its not a fail
 
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Check for air leaks using carb cleaner around all inlet connections with engine running if idle increases you have found your air leak. If no leaks are found clean throttle body but dont manually force open use ignition on and throttle pedal down (engine off!).
Egr could also be the culprit!

If its passed mot does light stay off long enough to satisfy the tester?
 
Edwrai said:
I think the originals are NGK I know from experience that there are differences and eurocarparts for example sell o2 sensors that aren’t correct for this engine


Sent from my iPhone using Tapatalk
Click to expand...
I notice there is no one very local to Dudley on the scan register, so try posting a new topic, "VCDS Near Dudley, West Midlands?"
Not everyone who can scan your car is on the list.
I'd think an incorrect sensor, as @Edwrai suggested is most likely.
Good luck.
Mac.
 
Cheap and cheerful possibility - is there any oily residue around the oil cap on top of the crank case? We had a recent minor recurring 'air leak' issue that was solved by replacing the oil cap with a new Febi one ordered overnight off Amazon Prime for £1.20 - the seal in the existing lid had shrunk and it wasn't squeezing hard enough against the seat to form a reliable seal (it would abruptly fault while warming up but only every so often)

The symptom with ours was while idling, abruptly it would cough then put on EPC and ABS lights and start revving up and down around the idle ; the ABS light could be cleared, but the EPC wouldn't go away and gave various faults that were identified here as being suggestive of air leaks causing the lambda / mixture sensing to go haywire trying to sort the mixture out.

Look for this -

febi bilstein 02113 Oil Filler Cap

on Amazon or Ebay.
 
@MariaE says the car runs well, and the emissions at the tail pipe are fine, so it seems to me very likely to be a sensor issue, not an actual emissions issue. EML will trigger for a faulty sensor (and other things too).
VCDS would, probably, confirm this.
Mac.
 
Thanks for your help its passed the mot cos the emissions were spot on but the light has come back on we will keep going with it
 
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