Regen frequency

gard_ian8

Active Member
Mar 5, 2007
174
0
I am beginning to think I have bought the wrong car...

I work form home and only drive about 3 miles each way to drop the kids off at school in the morning.

I have noticed the fans on every 3 weeks or so which i am sure is the dpf regen kicking in.

what is the normal time between these cycles?

I had a ODB reader to test the other day and I noticed that the soot content was 0.040 and it said a replacement wasn't due until this reading was at 0.125.

does this regen thing harm the engine or dpf in any way? is it something i can live with?

I think i should have bought a petrol for the amount of miles i drive, not a 2.0 TDI CR...
 

CRNeo

Active Member
Feb 5, 2016
394
3
Liverpool
I have 1.6TDI I do quite a lot of miles though - my regen cycles are around every 450-500miles.

Take a look at VAGDPF if you have an android phone you can use it to monitor DPF, see when it's active etc. quite useful.

Engine shouldn't be affected however if re-gen doesn't complete then you won't be burning off the soot and you'll end up with a blocked DPF. Also as far as I'm aware EGR usage increases during regen and EGR valves are another weak spot.

If the car has had the emissions "fix" that VAG rolled out then this is bad news as it increases regen frequency and increases EGR usage also - hence why lots of people have been having issues post fix - hence why I ended up getting my car re-mapped.

They are a good engine but yeah 3 miles each way is never going to complete a regen ever - you'll need to get right up to temp and give it a good blast down the motorway at least every now and again to even be in with a chance of clearing that DPF out - you may be right possibly not the best choice given your usage in hindsight.
 
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Legojon

I only wanted a remap
Staff member
Moderator
Jul 7, 2015
5,284
2,713
My FR used to regen like clockwork... however, I also did short journeys (2 miles to work). It went from 500 mile regens down to 250 down to 120. In the end, I blocked the DPF despite taking it for motorway blasts I didn't need to do each week.

In the end, I had to sell it and get a petrol :( That was despite driving extra miles when I knew a regen was about to happen. First warning sign for me was the oil level going up and stinking of fuel (the extra regen fuel gets dumped in the sump apparently).
 

weasley

Active Member
May 19, 2017
137
4
South Oxfordshire
During regen the engine pushes extra fuel through to burn in the DPF - this can lead to fuel dilution of the oil (as described above). In serious cases this thins the oil and dilutes the additives, reducing the protection it offers.

For a 3-mile each way journey, yes, you have the wrong car - your engine will never get up to temperature so the oil will always be operating at sub-optimal conditions and the parts will always be under-sized. Even a petrol engine will struggle to warm up fully in 3 miles (although they don't have to regen a DPF); maybe one of the small turbos might get hot quickly (eg the Ford 1.0l EcoBoost, which is designed to warm up quickly).

A 2.0 TDi is a lot of engine to heat up, and diesels run wide-open-throttle all the time, so lots of cold air runs through them. At idle and low loads there's not a lot of combustion going on, so heat isn't generated quickly. My Skoda Yeti with the 2.0 TDi CR 140 engine barely warms up in the winter during my 15 mile commute. That said, it doesn't regen often either (once every couple of months or so, at least those are the ones I notice). Every time you hear those fans it is the car attempting an active regan - you have interrupted it so it probably never gets a chance to complete the regen cycle. The DPF is probably not blocking yet simple because you're doing such low distance.
 

gard_ian8

Active Member
Mar 5, 2007
174
0
cheers for the replies lads, been ill so just started to look at this again.

I have downloaded the app mentioned above and i can see that it last did a regen 205 miles ago and its showing 58% full, im amusing this means its about 400 mile regen. its still running after i turn the engine off, did it again tonight. the app has the timer icon on and the help says this is a indication of a field regen is required. im going to give it a blast out tomorrow. what type of speed / revs and mileage should i looking at?
 

t121anf

Newbie
May 14, 2004
570
9
I have 1.6TDI I do quite a lot of miles though - my regen cycles are around every 450-500miles.

Take a look at VAGDPF if you have an android phone you can use it to monitor DPF, see when it's active etc. quite useful.

Engine shouldn't be affected however if re-gen doesn't complete then you won't be burning off the soot and you'll end up with a blocked DPF. Also as far as I'm aware EGR usage increases during regen and EGR valves are another weak spot.

If the car has had the emissions "fix" that VAG rolled out then this is bad news as it increases regen frequency and increases EGR usage also - hence why lots of people have been having issues post fix - hence why I ended up getting my car re-mapped.

They are a good engine but yeah 3 miles each way is never going to complete a regen ever - you'll need to get right up to temp and give it a good blast down the motorway at least every now and again to even be in with a chance of clearing that DPF out - you may be right possibly not the best choice given your usage in hindsight.

What obd 2 are you using with this?
 

CRNeo

Active Member
Feb 5, 2016
394
3
Liverpool
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gard_ian8

Active Member
Mar 5, 2007
174
0
Took the car out today with the vagdpf app open car started a regen so drive further until it completed. Reduced to 24 percent full down from 74 so happy with that. Will keep it in mind to do more miles more often.

Sent from my SM-A510F using Tapatalk
 
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