No DPF regen on long journey? Is that good?

No DPF regen on long journey? Is that good?

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IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
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Hi,

So when I got this car 2010 S80 almost 5 months ago I was a bit wary of it being a diesel and that I only do short trips. I drive 11.5 miles which is usually 17 minute drive to work in the morning and then back at night. I've only bought the better fuels and put in lucus upper cylinder lubricant once on a full tank. Last week I drove 42 miles it sat there fore two hours and then drove the 42 back. I was expecting it to do a regen but nothing apparently happened. Is this meaning my drive to work was fine or did it not hit the appropriate parameters to get to regen?

ConnectionError

1,946 posts

76 months

Sunday 17th April 2022
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How do you know it didn’t regen?

stevemcs

8,989 posts

100 months

Sunday 17th April 2022
quotequote all
It will carry out a regen when its collected enough soot and then only if all other conditions are met.

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
ConnectionError said:
How do you know it didn’t regen?
I had read somewhere its supposed to tell you to not turn your engine off (until completed)?

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
stevemcs said:
It will carry out a regen when its collected enough soot and then only if all other conditions are met.
What conditions? I would have thought after almost 5 months of five days a week driving except for 2 weeks holiday it would have had enough soot? So anyway how often does a car used for short journeys usually want to do a regen?

Thanks for your responses.

cuprabob

15,701 posts

221 months

Sunday 17th April 2022
quotequote all
IAmTheWalrus said:
ConnectionError said:
How do you know it didn’t regen?
I had read somewhere its supposed to tell you to not turn your engine off (until completed)?
On my VW, you only know it's doing a regeneration because when you stop the tick over is slightly raised and the engine sounds different. If you do happen to switch off while a regeneration is in process, the radiator fan runs on for 5 mins after you switch off.




IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
cuprabob said:
IAmTheWalrus said:
ConnectionError said:
How do you know it didn’t regen?
I had read somewhere its supposed to tell you to not turn your engine off (until completed)?
On my VW, you only know it's doing a regeneration because when you stop the tick over is slightly raised and the engine sounds different. If you do happen to switch off while a regeneration is in process, the radiator fan runs on for 5 mins after you switch off.
Well someone on here said to me if you turn the engine off before the regen completes it dumps a pint of diesel into your engine oil, I don't know if they are pulling my chain or not but it certainly sounds VERY bizarre. I mean, WHY?? I was under the impression it throws more fuel at the DPF if you are doing a regen, so why should it need to put it into the engine oil?

stevemcs

8,989 posts

100 months

Sunday 17th April 2022
quotequote all
IAmTheWalrus said:
What conditions? I would have thought after almost 5 months of five days a week driving except for 2 weeks holiday it would have had enough soot? So anyway how often does a car used for short journeys usually want to do a regen?

Thanks for your responses.
My 2.2 Mondeo on does 5 miles a day, there is no warning that its carrying out a regen other than if you stop the fan continues to run and the car seems very hot. I have had no issues so far, i'd just go with if it hadn't carried out a regen you would have known by now.

Oh and yes the Volvo does - on the D5 dump the fuel into the engine oil, there is usually a warning to tell you to under fill the engine oil on these engines.

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
Why does it have to dump fuel into the oil? I've never heard of this process. How does one under full it. It can't be advice from the manufacturer to underfill when they tell you how much torque put in.

stevemcs

8,989 posts

100 months

Sunday 17th April 2022
quotequote all
IAmTheWalrus said:
Why does it have to dump fuel into the oil? I've never heard of this process. How does one under full it. It can't be advice from the manufacturer to underfill when they tell you how much torque put in.
You under fill the engine oil, you sometimes find it written on the plastic engine cover. Once it starts the DPF regen process it uses the diesel to wash the DPF clean once its at a certain temperature, every system is different but the way Volvo designed it on the D5 is if the DPF regen fails for any reason the fuel is dumped back into the engine, weakening the oil dilution and raising the level.

It sounds like you have nothing to worry about, just keep up to date with the oil changes, use good quality fuel and keep the fuel level topped up, and then a good run once a month should see you ok.

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
stevemcs said:
You under fill the engine oil, you sometimes find it written on the plastic engine cover. Once it starts the DPF regen process it uses the diesel to wash the DPF clean once its at a certain temperature, every system is different but the way Volvo designed it on the D5 is if the DPF regen fails for any reason the fuel is dumped back into the engine, weakening the oil dilution and raising the level.

It sounds like you have nothing to worry about, just keep up to date with the oil changes, use good quality fuel and keep the fuel level topped up, and then a good run once a month should see you ok.
Thanks. So it does put fuel into the engine, is it really a pint? a pint of fuel sounds like a lot. Car runs fine but there are a couple of weird issues I have with the readings for fuel and mph, it says I average 30mph or so mph despite the fact I do 30 mph to get out of the village and onto the dual carriage way for about two minutes, I then spend 15 minutes on the dual carriage way at 62mph or so and then I come off the dual carriage way and a few hundred yards to where I work. So that is not remotely an average of 30mph. It also says I average 40mpg, yet, the display shows this at 30mph and far better when on the dual carriage way. Is there anything I should be concerned about? Is this a car that learns driving style?


stevemcs

8,989 posts

100 months

Sunday 17th April 2022
quotequote all
about 0.5 to 1.0 in terms of overfill.

I wouldn't be to concerned about the average fuel it will have no impact on the DPF, you could always reset the average fuel/speed.

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
stevemcs said:
about 0.5 to 1.0 in terms of overfill.

I wouldn't be to concerned about the average fuel it will have no impact on the DPF, you could always reset the average fuel/speed.
Hi,

thanks for your response, 0.5 to 1 of what? Pints?

Do you know how to reset average fuel/speed? Thanks for your help.

stevemcs

8,989 posts

100 months

Sunday 17th April 2022
quotequote all
Litres, and no idea on the reset as it would depend on year/model, but normally through the car menu - either screen in the centre console or using the left hand stalk

E-bmw

9,971 posts

159 months

Sunday 17th April 2022
quotequote all
IAmTheWalrus said:
Is this a car that learns driving style?
Not quite sure what you are getting at here.

Some autos allegedly learn your shift pattern/acceleration rate in an attempt to keep you in the right gear, but not sure what context you are talking about as you seem to be talking about average speed & economy?

Glosphil

4,502 posts

241 months

Sunday 17th April 2022
quotequote all
Easy enough to check the accuracy of the average speed readout. Just divide journey length (in miles) by journey time (in hours).

IAmTheWalrus

Original Poster:

1,049 posts

51 months

Sunday 17th April 2022
quotequote all
E-bmw said:
IAmTheWalrus said:
Is this a car that learns driving style?
Not quite sure what you are getting at here.

Some autos allegedly learn your shift pattern/acceleration rate in an attempt to keep you in the right gear, but not sure what context you are talking about as you seem to be talking about average speed & economy?
My old BMW held a record of driving behavior, it was such that if you left it with someone for a while you would certainly notice it when you got back in the car. I want the car to be economical.

E-bmw

9,971 posts

159 months

Monday 18th April 2022
quotequote all
IAmTheWalrus said:
I want the car to be economical.
Just drive it economically & it will be economical.

stevemcs

8,989 posts

100 months

Monday 18th April 2022
quotequote all
If you want economical on a short trip buy a Renault Zoe or VW Up, both will be far better on fuel. My Mondeo averages 25mpg locally

E-bmw

9,971 posts

159 months

Monday 18th April 2022
quotequote all
Good point, a diesel will pour fuel into the engine for the first couple of miles until it is warmed up, only then do they become economical.

Hence why immediately after start up the "range to tank empty" takes a dive for the first few miles & then comes back after a few more miles.