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Audi A3 2.0 PD 2007 - Particulate lamp on - Fixed #

Posted by Mark Robins on March 1, 2010, 8:57 pm

Year of Manufacture *: 2007
Engine Code or CC *: 2.0 PD

Vehicle came to me after having new cat particulate filter, unable to extinguish particulate filter lamp on dash. No fault codes logged, ECU reset for new filter, no blockage indicated on live data.
Tried a forced regen out of desperation, am I missing something?

Thanks in advance.

Re: Audi A3 Particulate lamp on.

Posted by Steve Gittins <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1086' width='330' height='300' border=0 style='border:none;'> on March 2, 2010, 7:43 am, in reply to "Audi A3 Particulate lamp on."

Not had much to do with VAG particulates but had plenty of trouble with faulty sensors on the PSA stuff not showing any differential between front and rear of filter (As if there is no filter). They expect to see a small amount of restriction/pressure difference so it flags a fault.

HTH.
Steve.

Re: Audi A3 2.0 PD 2007 - Particulate lamp on # (Update)

Posted by Mark Robins <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1448' width='330' height='300' border=0 style='border:none;'> on March 22, 2010, 4:30 pm, in reply to "Audi A3 2.0 PD 2007 - Particulate lamp on #"
Mark Robins

Had the car back in finally and is logging 008194 (P2002) Particulate trap bank 1: Efficiency Below Threshold.
I found out that it’s had a new particulate filter (although not a genuine one), I’ve scoped the output from the differential pressure sensor and with a quick rev it peaks at 2.0v. I tried a pressure gauge in the pre filter pipe at the sensor and that show 3psi with a moderate blip of the throttle (won’t rev above 3000 it’s in limp mode) live data is indicating 250 mb which according to my math is 3psi, so I figure the D.P.S. is OK. Anybody got any ideas what pressure is permissible? My thoughts are the filter is faulty. I know that if I had similar readings on a petrol cat car the cat would be faulty, but I'm not sure about diesels.

Fixed #

Posted by Mark Robins. on March 23, 2010, 8:35 am, in reply to "Audi A3 2.0 PD 2007 - Particulate lamp on #"
Message modified by board administrator March 24, 2010, 2:40 pm

New DPF was blocked, just because it's new doesn't mean it's OK.

Fixed #

Posted by Tony Attwood on March 23, 2010, 6:21 pm, in reply to "Re: Audi A3 2.0 PD 2007 - Particulate lamp on # Fix"
Message modified by board administrator March 24, 2010, 2:41 pm

Hi Mark,
What was the pressure reading before DPF after you fitted new unit.
I did not think that 3 psi was a high reading at all with the non genuine unit fitted.
I have seen 40 to 50 Kpa (6 - 7 psi) on Zafira's before re-gen without bringing on the service light.
After Re-gen these run around 3 - 6 Kpa on a light to medium throttle.
The Zafira system seems to reach 80 Kpa (11-12 psi) before service light comes on relating to the differential pressure.

Cheers, Tony.

Fixed #

Posted by Mark Robins on March 23, 2010, 7:15 pm, in reply to "Re: Audi A3 2.0 PD 2007 - Particulate lamp on # Fix"
Message modified by board administrator March 24, 2010, 2:41 pm

Hi Tony,

I haven't actually changed the DPF as it was under warranty by another garage, but I have been reliably informed that 250mb on live data was too high. Matthew Booth who posted that he uses a manometer to check differential pressure said this "Typical back pressure is about 100mbar. Measuring the difference between pre and post filter I would expect to see less than 100mbar difference. Any more and I would consider the filter to be clogged/faulty."
I will be re-testing the car when it comes back and will post the new figures. I talked to the actual manufacturer of the DPF and he is adamant that there is something wrong with the engine causing the DPF to block so quick. I have recently found out that this is the second DPF fitted in as many months, so the story will continue no doubt!

Fixed #

Posted by Kevin Apps on March 23, 2010, 8:13 pm, in reply to "Re: Audi A3 2.0 PD 2007 - Particulate lamp on # Fix"
Message modified by board administrator March 24, 2010, 2:41 pm

Mark.
Fuel part,s ???
Kev.

Fixed #

Posted by Mark Carter on March 23, 2010, 9:29 pm, in reply to "Re: Audi A3 2.0 PD 2007 - Particulate lamp on # Fix"
Message modified by board administrator March 24, 2010, 2:41 pm

HI Mark, have you got a temperature for the DPF in live readings and if so what is it?

Regards Mark

Fixed #

Posted by Mark Robins on March 24, 2010, 12:10 am, in reply to "Re: Audi A3 2.0 PD 2007 - Particulate lamp on # Fix"
Message modified by board administrator March 24, 2010, 2:41 pm

Sorry Mark I did look at temp readings but can't remember what they were (actually removed and tested sensors with hot air gun while monitoring live data ) but didn't now how to interpret what temp readings meant, DPF's are new to me. Kev I'm not sure if it was F.P. DPF but the guy I talked to was in Nottingham and his name was Ashley (seemed quite knowlegable)he said they make a lot of DPF's for taxi firms and the substrate is O.E.M. sourced.

Re: Fixed #

Posted by Tony Attwood <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3025' width='330' height='300' border=0 style='border:none;'> on March 25, 2010, 12:08 am, in reply to "Fixed #"

Hi Mark,
Coincidentally, I had a Zafira in today with a blocked DPF.
I heard it coming, from down the road, hissing like a hissy thing.
The rubber hose connecting the pre DPF pipe to the sensor had split with the excess pressure.
One of the DTC’s was for the EGR valve. A quick check of live data showed it staying open.
EGR position, along with air mass nominal and actual readings.
Replaced the EGR valve and took it for re-gen drive.
This DPF had blocked due to the EGR valve staying open, therefore reducing the exhaust gas temperature and not allowing re-gen to take place as the exhaust gas would not reach the high temperature required.

This is one possible reason for your Audi blocking the DPF.

Screen shot of data whilst re-gen in progress below.
Differential pressure of 26 Kpa is with the split hose still in place!!
I had not changed it as I know this Vauxhall system will still re-gen even if there is no pressure signal to the ECU.
As can be seen by the last attemp to Re-generate just 25 KM ago.

(The VAG system reverts to a mileage and hours usage format if it loses any one or more of several different signals.)

Also, due to the pressure, the replacement would only burst or blow off during the drive.
The exhaust temp of 744 Degs C is the highest I have seen so far, previous highest was 660 Degs C.

The second screen shot is from when I got back & replaced the hose.
With the engine at idle this Vauxhall now has a differential pressure of just 1 Kpa, even with a 20% blocked DPF.

Cheers, Tony.

P.S. Admin people, that 'upload image' button works so smooth & easily.

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