Emmisions Control System

**SuperCharger28** · 14-10-2011,04:41 PM

Hello,

This morning the emmisions control system light came on my vehicle. It is a Apr/May 2008 A6 2.7 Le Mans edition and I was just wondering if these vehicles have a DPF fitted? If I accelerate hard I can usually see some smoke behind me. I'm really hoping that this is not serious or expensive to fix. I've read it could be something as simple as a sensor which is about £100 max.

P.S - its done 58,500 miles

Any ideas?

Thanks!

**AxeMurderer** · 14-10-2011,05:21 PM

The light 'just' means there is a persistent engine fault. You should get the codes read to find out what it actually is.

Mine is lit because of the swirl valve linkages. These can only be obtained as part of new inlet manifolds and at £2K they are staying unfixed. Hopefully yours is something cheaper.

**SuperCharger28** · 14-10-2011,05:46 PM

What are your symptoms?

**AxeMurderer** · 14-10-2011,06:41 PM

There are no symptoms I can detect. Fuel economy seems unaffected on longer journeys, but might be marginally worse on short ones.

But you need to get your codes read as it could be anything (well, any of a number of things).

**Brycie** · 14-10-2011,06:42 PM

Just another possibility, my problem started after around 60-65k on the clock - emmissions light came on, heavy black smoke out of the rear & intermittently the turbo would fail to kick in (the turbo problem would go away at first when I stopped & restarted the engine). As you've not mentioned your car losing power I hope your problem isn't the same as mine, but mine was due to a split in the intercooler.

When I had this problem & asked for help on here, people were suggesting that based on my symptoms I should also check the all the pipes and the MAF meter, so it may be worth checking those.

Hope your problem is simple & cheap to fix.

Cheers,
Paul.

**Dpanic** · 14-10-2011,08:02 PM

Hi,

have you any loss of power?

Take the Engine plastic cover off (just pull .. only clipped on) and check your rubber hoses to and from the EGR valve - check for splits!

Then do the same for the turbo, take the intake hose off and look at the fly wheel on the turbo - any oil

But as the rest of the chaps say, it needs the code read to be sure.

**Blackavant** · 14-10-2011,08:11 PM

My EGR sensor failed 2 weeks ago on my 2010 2.0tdi, luckily still under warranty. There was no idication of a problem other than the engine fault light came on, called out Audi roadside and the guy says its a common fault and the new sensor is an upgrade. Seems to be an issue caused by the AC unit?????

**SuperCharger28** · 14-10-2011,08:34 PM

I will do the checks in the morning. And no I've not noticed any loss in power. It still pulls like a train and is smooth throughout the power. Where abouts is the EGR valve located?

Thanks.

**Dpanic** · 14-10-2011,10:06 PM

It's just to the left of the passenger side bank, silver module - lines feed to and from - the from goes to a intercooler I believe.

Sorry hard to explain, others might explain better - I'll take a pic and post it from my 3.0dti - same layout I believe if you cannot locate it.

But as you have no loss of power, it's not going to be this - mine when into limp mode (trip gear box - 40mph max) until EGR was replaced £300 - then hose went after £20 (free from Audi - as they broke it swapping the valve)

Regards - rob

**SuperCharger28** · 14-10-2011,10:21 PM

Right. Took it out with a lead foot and my god it has lost some power. I can't believe it. It's only been the missus that has been driving it the past few weeks and I doubt she noticed. (im on a manual) and the engine does sound a bit louder overall I am really praying now that its not the turbo. Can an EGR be replaced by your average joe?