What a day... Emissions?

[god_thats_quick]

Hi All,

Well I wasn't expecting that, car failed it's MOT today for emissions, Carbon monoxide was too high (by a lot) and lambda was a little low (only just outside limits) any ideas what could be causing this?

I'm guessing it's either lambda sensor / cat related but thoughts or experiences would be most welcome!

Cheers,

Ben.

 

[simch]

try a different mot station. this is common and some mot'ers chose not to do the second test that they are allowed to.

if a car fails firstr basic test, (a lot do) the tester should go to a fast idle test that takes about three minutes to do, revving tha car at 2500 revs for that time. To fail this test, your car would be running like a ****!

So if he did not do the crazy long fast idel, he may be trying it on, to sell you new cats or somethign, and it may just be worth goingto a better tester.!!

 

[god_thats_quick]

umm... hate to say it but I don't think they were taking the ****, I've got last years test and this years to compare (same place too and I don't think they're like that), the fail notice shows that they completed both fast idle tests and it failed both quite spectacularly on the monoxide front (1.8%).

Anyone know if knackered cat is the most likely cause?

 

[simch]

did you see them do it.......? Was it real red hot warm (engine) doing it.....?

My mate is an MOT tester, he reckons he can get nearly anything through if he wants to........!!

Well my 2 lite rally spec mk2 thaqt ticks over at 1800 revs gets through each year........! It runs like a dog afterwards til I change it all back, but you may just meed a more friendly tester......!?!?

 

[god_thats_quick]

Well I made sure I got the car up to temp before I got there and the car wasn't sitting for long so I'm guessing there really is something up.

Your probably right about finding a friendlier tester, however I'm more worried that it's gone from 0.1% last year to 1.8% this year.

 

[simch]

if you have a blanking hole in the dp after the lamda probe, undo it a bit and bleed some air in there!! That'll get it through!
If the cae goes ok, 1.8% is harldly gunna melt the ice caps. The lmit a few years back was 3.5%...

 

[god_thats_quick]

Someone else must have actually had this issue on an S3, no?

 

[simch]

has it been mapped? Maybe try cleaning your maf......?

 

[god_thats_quick]

nope it's standard I guess checking the MAF / Lambda is where to start, just thought I remembered at least one person on here having this issue (or similar) but can't find the thread.

 

[god_thats_quick]

Just incase anyone was interested, it turned out to be the Lambda sensor - a big thankyou to Adam at AmD for checking it out on saturday morning, fitted the new sensor after the local Audi place actually having one and the car passed it's emissions this morning with virtually no CO and no registered HC emissions.

 

[VeeDub Geezer]

Lambda probes are prone to go after around 60k

they are classed as a service item