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gdallas
10-09-2013, 07:33 PM
Couple of queries here!

Have been becoming concerned that my car has forgotten how to regen. Could be my OCD! Lol was sitting at 24g the other day, which I felt was rather high. Just so happened to bee working in Aberdeen today, which meant a 100mile each way up the A90 at 75-79mph. for the first half hour I drove in 4th to keep th revs over 2k. when I arrived home, I measured the soot, it was only blooming at 10g! and this is where my ocd may be kicking in, doesn’t this seem high, following a large journey like that?

some hours later I strapped on the vcds and took it up the motorway for 20 mins, I watched in realtime the soot go all the way down to 1.91g then it kinda bottomed out. What I noticed tho was as I arrived at junction, or whacked it on neutral, any time where there was very low revs, the measured soot began to climb farily rapidly actually. And within a 10 seconds, maybe about 2g. is this normal?

Now, my ignorance here is with reagrds when a regen has completed, or even started, or what actually defines a regen in the first place. I’ve measuring my soot a lot recently, it looks as though my car continuously burns off soot when the conditions are right, i.e. about approx. +2k revs where the exhaust gas temp must be sufficient to burn it off. However, as far as I can glean from my experiments, although my car appears to be continuously regenerating, it only appears to regenerate IF the soot levels fall below a particular low level as my “time/distance since last regen” status is still of large values.

Now I’m particularly concerned as I would have assumed a 2.5 hours journey each way to Aberdeen on a 70 should have “regenerated” the dpf, like completely? That and the fact why soot levels climb back up rapidly scares me a little!

It may be related to me not having adapted my dpf sensor, but im not sure

Guest 2
10-09-2013, 07:54 PM
The adaption could have something to do with it, I can feel my DPF doing its thing ~40% full on VCDS. This is only once every 2.5 weeks tho.

All other times its normal and I do one run a week in 4th just to help it along. I do 600 miles a week, 100% motorway, no town.

gdallas
10-09-2013, 08:02 PM
How can you tell from vcds that's it's 40 percent full?

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Guest 2
10-09-2013, 08:04 PM
It's group 75 in Engine Measuring Blocks .. I'll go out and screen shot now.

Guest 2
10-09-2013, 08:09 PM
3rd box along - currently 22.9% full of soot or whatever it is.

Btw - A PM to Crasher would prove useful as he knows his ash from his soot and can advise better than me!

http://i816.photobucket.com/albums/zz90/57_audi/A3/a3dpf_zps8b5d2947.png~original

gdallas
10-09-2013, 08:18 PM
Ah, what a peculiar name to call it ...

Cheers Bro. I'll check mine now

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Guest 2
10-09-2013, 08:19 PM
Thats on my 1.9 A3, I can't see it being much different to your A4, as I said above, maybe a PM to Crasher would prove useful as he knows alot about DPFs and loves(!) them!

gdallas
10-09-2013, 08:24 PM
********! Can u believe my measuring blocks are greyed out. Damn! Cheers anyway Chris


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Guest 2
10-09-2013, 08:27 PM
********! Can u believe my measuring blocks are greyed out. Damn! Cheers anyway Chris


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How did you measure the soot if the Measuring Blocks are greyed out?

s7gpt
10-09-2013, 08:29 PM
chris, does the engine have to be running to get that reading ? , starting to feel my OCD kicking in now and wish id not read this ;)

Guest 2
10-09-2013, 08:30 PM
Nope, ignition on only.

Seems on the B8 you need to have a peek at group 108 and 241 according to RT - sorry for any confusion :o

gdallas
10-09-2013, 08:31 PM
I measured it in advanced measuring values I think it was called. I selected number 196 on mine from the list. I took a video , once it's uploaded I'll show u my soot ramp up... Doesn't that feel right to me

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s7gpt
10-09-2013, 08:32 PM
Nope, ignition on only.

Seems on the B8 you need to have a peek at group 108 and 241 according to RT - sorry for any confusion :oCheers Chris although not sure what the peek thing you mention is :Blush2:

s7gpt
10-09-2013, 08:33 PM
Cheers Chris although not sure what the peek thing you mention is :Blush2: just got it, you mean look :)

Guest 2
10-09-2013, 08:33 PM
peek as in look (you need to have a look at ... ) ... are you on the :alcoholic ? ;)

gdallas
10-09-2013, 08:43 PM
Right.... Tell me this is normal. And I'm not talking about my music choice! soot - Google Drive (https://docs.google.com/file/d/0B6sHdL0miFwISEU3SHg2Q3otNWs/edit?usp=sharing)

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Guest 2
10-09-2013, 08:44 PM
I don't think thats normal - shouldn't be going up as quickly as that I'm sure?

I'll check mine in a few mins, wife took the car out.

gdallas
10-09-2013, 08:45 PM
Ye I'd say!

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s7gpt
10-09-2013, 09:19 PM
I measured it in advanced measuring values I think it was called. I selected number 196 on mine from the list. I took a video , once it's uploaded I'll show u my soot ramp up... Doesn't that feel right to me

Sent from my Nexus 4 using Tapatalk 2 bit of a vcds newbe but if you give me the step by step buttons to press I can try and check mine on my drive to work tomorrow and see how they compare to your vid etc

theskyfox
11-09-2013, 08:50 AM
Out of interest Chris, you mentioned earlier that you occasionally leave your gear in 4th, I'm assuming that the 2.0TDi will still regen in higher gears than that still too? I know on my 3.0TDi my DPF regens will happen in 6th gear too.

-Andrew

Guest 2
11-09-2013, 08:55 AM
My A3 is only 5 speed, 70 in 5th is 1600rpm so its not really getting a chance to raise the temp. 70 in 4th is about 2400rpm, your 3.0 should regen fine in 6th or 5th due to the engine being bigger and producing more heat in the exhaust than my poor-mans 1.9.

s7gpt
28-09-2013, 07:37 PM
checked mine 4.6grams today for what its worth ?