MOT Failure emissions

[BRG_GTI]

Hi everyone

I am new to the forum but have owned my S3 for 4 months now. I have just had an mot done on it and it failed on emissions.

I have had it plugged into the computer at the garage where it failed and there is no logged fault codes.

I have serviced the car with new plugs, filters, oil and also a fuel cleaning liquid. I have taken the car on some long runs to see if that would clear it.

I took the car back to the garage for an emissions test and again it failed on fast idle with too much CO2 but was ok on tick over

Does anyone have any clues as to what I can check before having to get the garage to look at it.

Any help would be much appreciated ?

 

[jojo]

I have serviced the car with new plugs, filters, oil and also a fuel cleaning liquid. I have taken the car on some long runs to see if that would clear it.

Was you driving like Miss Daisy or Fernando Alonso style? And what mileage is the car on?

Best to drive the car hard on the way to the MOT station, and I mean hard as in WOT in 3rd gear to the redline a few time hard, with in the legal speed limits of course, then try and get your emmissions checked whilst your cats are fully warmed up!

 

[Maz]

I'm guessing maybe a dodgy 02 sensor if it failed on emissions.

 

[BRG_GTI]

miss daisy hahaha no I made sure to give it plenty of revs only within the speed limit of course

I had made sure it was warm on both occasions but it still was way out.

Can you give me any idea of what kind of price you think I should be paying for a garage to look at it or is that a how long is a piece of string type question ?

 

[mk1chopper]

Audi offer free health checks might be worth taking it to them and seeing if they find anything:

Audi Health Check < Maintaining your Audi < Owners area < Audi UK

To look at your car an hour's labour max, you might be able to negotate on this, i.e. some places will do the check for free if you have them fix the fault

 

[BRG_GTI]

Thanks for the advice on the health check. I just had a look to see what it covers and it appears to be more service related items which i have just changed it may be an idea to contact them with the problem I am having and see what they can advise.

 

[aragorn]

What were the exact figures. All of them.

If it was JUST high CO and everything else was fine, your cats are probably dead (or missing)

Other issues like broken lambdas or airleaks usually cause other values to change as well.