DPF issue ?

[Mutley2110]

Hi, I’ve purchased an Audi A4 2.0 tdi Avant tech SE a few months ago.  It’s a 2015 model with 57k miles.  A week after picking it up at the dealer when I parked up the fan was running, I called the dealer and they sent a mechanic out who explained it was burning off the DPF and it does this regularly. 
I’ve driven diesels for 30 years and have never experienced this before. However, this is used as a ‘second car’ that 90% of the time only does about 5 miles per day and the remainder is runs of 100 miles +. MPG and performance is excellent. 
The dealership advised it is due to the low usage but I’m wondering if it’s true or if the DPF should have been replaced when I first noticed the problem. 
some weeks it’s happening after every journey. 
any advise would be greatly appreciated. 
regards. 

[Brizzle]

It seems perfectly normal to me 

With my car if I hear the fans on after I turn it off I know it’s time to take it for a blast on the bypass near me , but I normally take it for a good spin every Friday after work as I finish early and the motorway is only 5 mins  from me 

It the same with our brand new work vans, one had only 159 miles on clock and fans kept staying on when off, but once’s it’s been for a good drive they are fine 

[Stevey Y]

2 hours ago, Mutley2110 said:

Hi, I’ve purchased an Audi A4 2.0 tdi Avant tech SE a few months ago.  It’s a 2015 model with 57k miles.  A week after picking it up at the dealer when I parked up the fan was running, I called the dealer and they sent a mechanic out who explained it was burning off the DPF and it does this regularly. 
I’ve driven diesels for 30 years and have never experienced this before. However, this is used as a ‘second car’ that 90% of the time only does about 5 miles per day and the remainder is runs of 100 miles +. MPG and performance is excellent. 
The dealership advised it is due to the low usage but I’m wondering if it’s true or if the DPF should have been replaced when I first noticed the problem. 
some weeks it’s happening after every journey. 
any advise would be greatly appreciated. 
regards. 

The fans work after a regeneration even an aborted one its easy to spot the onset of regeneration as the revs are higher at idle and the engine sounds a bit harsh, it sounds like yours is constantly trying to regenerate but can't because of the short milage, aborted regeneration causes a wealth of problems as the extra fuel injected in this process has no where else to go except past the rings and into the sump oil ,if you notice a regeneration start just carry on driving for 15mins to allow to finish, the fan will still be working for about 10mins after this is to cool the engine bay and stop you lighting up the drive, when you consider that to regenerate the fuel ratio is upped which brings the start temp in the DPF to about 650c to burn the soot away.

Steve.

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[Mutley2110]

1 hour ago, Stevey Y said:

The fans work after a regeneration even an aborted one its easy to spot the onset of regeneration as the revs are higher at idle and the engine sounds a bit harsh, it sounds like yours is constantly trying to regenerate but can't because of the short milage, aborted regeneration causes a wealth of problems as the extra fuel injected in this process has no where else to go except past the rings and into the sump oil ,if you notice a regeneration start just carry on driving for 15mins to allow to finish, the fan will still be working for about 10mins after this is to cool the engine bay and stop you lighting up the drive, when you consider that to regenerate the fuel ratio is upped which brings the start temp in the DPF to about 650c to burn the soot away.

Steve.

 

Hi Steve, thanks for the info.
To be honest, I’m unable to notice a regeneration start as the car seems to drive the same at all times! and there’s times when I’m unable to continue driving for another 15 mins.
I do drive my diesels fairly ‘hard’ as I tend to not change gears until around 2000rpm, and I presume this may be why I’ve never experienced this in my other diesels that are driven all day?
When you mention’ a wealth of problems’ - if this persists, what could I be faced with?  
Would a new DPF resolve the problem? As I presume at 57k miles it’s still the original??

regards. 

[Brizzle]

25 minutes ago, Mutley2110 said:

Hi Steve, thanks for the info.
To be honest, I’m unable to notice a regeneration start as the car seems to drive the same at all times! and there’s times when I’m unable to continue driving for another 15 mins.
I do drive my diesels fairly ‘hard’ as I tend to not change gears until around 2000rpm, and I presume this may be why I’ve never experienced this in my other diesels that are driven all day?
When you mention’ a wealth of problems’ - if this persists, what could I be faced with?  
Would a new DPF resolve the problem? As I presume at 57k miles it’s still the original??

regards. 

You can get a DPF cleaner you put in your diesel that helps if you do short journeys 

[Stevey Y]

19 hours ago, Mutley2110 said:

Hi Steve, thanks for the info.
To be honest, I’m unable to notice a regeneration start as the car seems to drive the same at all times! and there’s times when I’m unable to continue driving for another 15 mins.
I do drive my diesels fairly ‘hard’ as I tend to not change gears until around 2000rpm, and I presume this may be why I’ve never experienced this in my other diesels that are driven all day?
When you mention’ a wealth of problems’ - if this persists, what could I be faced with?  
Would a new DPF resolve the problem? As I presume at 57k miles it’s still the original??

regards. 

Hi the problems you will encounter are oil degradation [Dilution] due to the fuel getting in and a possible blocked DPF, at the milage you have the DPF is still young enough to survive if treated now and as Karl pointed out if you use a good fuel additive that helps no end, my pet love is Hydra Maximus which I have used on all my cabs to good effect and never had a new DPF which leads me to your comment about the previous diesels you have had, the key term being all day, this is the same as my current car which might regen every other day, but I am doing between 70-140 miles a day, big difference, five miles a day mostly won't hack it as the engine will get up to temp and initiate a regeneration which is promptly stopped, the car will seem a lot quicker when its doing a regeneration as the EGR is shut because the fuel/air mixture is a lot richer and won't need any polluting gasses from the EGR otherwise it won't cause the combustion in the DPF, I suppose in essence, use a fuel additive and give it a good kicking once a week for twenty miles.

Steve.