[pedroF31]

I've done 3,500 miles now and have never noticed any reduction in mpg, performance or revs etc.

On 2 occasions when I have parked and got out I have noticed the smell and the fan going, otherwise nothing.

Err, make that 3 - it did it again today !

[robwils]

Originally Posted by Brigand

But what would you do that is different if you knew th engine was doing a dpf and you are driving down M6, M1 etc?

There is only really one precaution you really need to take with a dpf regen.

As others have already said, keep driving till its finished. My trips are generally short with odd longer runs , so would be good for me to know exactly when its doing it and when complete.

[HighlandPete]

Originally Posted by JoshB25

I think you did the right thing buying a second hand diesel F30. With the low miles you do it will be more desirable when you come to sell it. My dealer said the DPF was an issue a couple of years ago on older models but not so much the case nowadays. I asked this same question when purchasing my old 2012 116d as at the time my commute was only 6 miles there and back a day but would increase within the next year. I think all will be fine.

How a garage know this when we have no data to support it, I don't understand. Hope it is improving, but only time will tell. It is cars as they age that are getting many of the issues as mileage/age accumulates. Although poor usage does accelerate some of the issues, like oil dilution problems. (See my next post).

HighlandPete

[HighlandPete]

Originally Posted by Thackers

With a manual gearbox Apart from :

1.the MPG Drop which at the time you may not notice

2. The apparent burning caramel smell

Are there any other symptoms?...I presume active the regen can't be completed with the car at Idle due the temperatures needed?

If you are sensitive to engine note/feel you may notice a gruff almost offbeat soundtrack.

The best advice is to continue until the regen' is complete. Regenerations can be interrupted and continue the next time the parameters are met. I've personally witnessed stopping mid regeneration, knowing I'm running again after a few minutes. On restart, within about half a mile the regen' will trigger again and go on to completion.

Idling or incomplete regenerations are where the issues come in. Idling is a cause of oil dilution during a regen', you don't want that too often or oil dilution tolerances will be overshot, and/or oil level will rise.

The extra heat for an active regeneration is obtained by an extra post injection phase, (heats the exhaust stream), so a working engine with load is better than an idling engine, where this extra fuel is not burned efficiently and can (and does) wash past the bores into the sump.

Talking with my local recovery guy, he has loads of issues with messed DPF regenerations. Worst case examples include oil dilution to the point of a break down in lubrication and con rods through the side of the engine. Runaway engine destruction (combustion fed from the diesel in the sump oil) or draining excess volumes of diluted oil. He told me one of the worst oil dilutions was over 100% extra in the sump, 'oil' now over 50% diesel.

HighlandPete

[....,,,,..,,..]

Originally Posted by HighlandPete

If you are sensitive to engine note/feel you may notice a gruff almost offbeat soundtrack.

The best advice is to continue until the regen' is complete. Regenerations can be interrupted and continue the next time the parameters are met. I've personally witnessed stopping mid regeneration, knowing I'm running again after a few minutes. On restart, within about half a mile the regen' will trigger again and go on to completion.

Idling or incomplete regenerations are where the issues come in. Idling is a cause of oil dilution during a regen', you don't want that too often or oil dilution tolerances will be overshot, and/or oil level will rise.

The extra heat for an active regeneration is obtained by an extra post injection phase, (heats the exhaust stream), so a working engine with load is better than an idling engine, where this extra fuel is not burned efficiently and can (and does) wash past the bores into the sump.

Talking with my local recovery guy, he has loads of issues with messed DPF regenerations. Worst case examples include oil dilution to the point of a break down in lubrication and con rods through the side of the engine. Runaway engine destruction (combustion fed from the diesel in the sump oil) or draining excess volumes of diluted oil. He told me one of the worst oil dilutions was over 100% extra in the sump, 'oil' now over 50% diesel.

HighlandPete

Wow that's a lot of diesel in the wrong place.

As I mentioned earlier one of main problems I know about is people setting fire to car or surrounding area.

Mr n mrs smith go to car boot sale / camp site etc.

Long trip - car does a regen towards end, they park up in longish grass ......

[HighlandPete]

Originally Posted by Brigand

As I mentioned earlier one of main problems I know about is people setting fire to car or surrounding area......

Jaguar had an issue with the first S type Jags with the diesel fitted, regens were doing damage/risk of damage to the underside of the cars. Had to modify the regeneration strategy to 'cool it' a bit.

The guy who I mentioned in the last post runs/works in a garage which have a special bay with fireproof floor and heat shields they put around the vulnerable parts when making forced regenerations. He said it is amazing the heat which comes off a stationary car revving away, making a forced regeneration.

HighlandPete

[lobeydosser]

I've done 7500 miles in 7 months now and have never been aware of a regen happening. Admittedly my car has tended to have had a decent run each month at motorway speeds so maybe its happened then,
The only thing i noticed once was that the exhaust note sounded lower, like a droning sound, for a few seconds, although I wasn't aware of any change of engine smoothness or power.
I just put it down to pulling up a long hill at steady speed with four adults and luggage on board.

[Chris Peacock]

My wife's F21 120d has only covered 4.5k miles in 9mths and not had a single issue, albeit it has been at the back of my mind it could cause issues.

As suggested the deal we got on the diesel was far stronger than the equivalent performance petrol car.

[....,,,,..,,..]

Originally Posted by Chris Peacock

My wife's F21 120d has only covered 4.5k miles in 9mths and not had a single issue, albeit it has been at the back of my mind it could cause issues.

As suggested the deal we got on the diesel was far stronger than the equivalent performance petrol car.

Personally, I would not worry too much about mileage as long as it's not all slow in traffic mileage.

My biggest concern is long term use of start stop technology, as a rule things fail when they change state between. Off and on.

[Blueyzfr169]

Originally Posted by Nick the Greek

With respect.
You've probably bought the wrong car.
Why diesel with such a tiny mileage.

LOVE the huge torque and tuneability of the Diesels, especially the 335d.....

[troggy1969]

I used to notice my 2015 335 regenning with the fan on when stopped but it's never happened on my 2016 one. Could have changed the software or maybe I'm just driving faster and it's all passive
Some nice hills round here to run up at full throttle

[Soul_Glo]

Originally Posted by Blueyzfr169

LOVE the huge torque and tuneability of the Diesels, especially the 335d.....

Holy thread revival batman.

[DriveS]

Here is a link to a thread which explains the parameters required for a regen on the E90 series. I doubt they have changed much.

http://www.bimmerforums.co.uk/forum/...ffice-t353042/

The main issue with DPFs clogging on the E90s was because of the short life and high failure rate of the 2 x thermostats. These would stay open, not allowing the engine to reach the required temp for a regen. There was no temp gauge and no DPF regen indicator, so people were completely unaware of what was happening. Until fuel consumption went up and the engine struggled at high revs.
I would like to think these issues have been prevented on the F30 series.

[SteveChester]

These "regens" are basically a clue to the fact that you aren't driving it hard enough!!

Take it out for a good thrashing and both parties win!!!

[Hooded]

Originally Posted by DriveS

Here is a link to a thread which explains the parameters required for a regen on the E90 series. I doubt they have changed much.

http://www.bimmerforums.co.uk/forum/...ffice-t353042/

The main issue with DPFs clogging on the E90s was because of the short life and high failure rate of the 2 x thermostats. These would stay open, not allowing the engine to reach the required temp for a regen. There was no temp gauge and no DPF regen indicator, so people were completely unaware of what was happening. Until fuel consumption went up and the engine struggled at high revs.
I would like to think these issues have been prevented on the F30 series.

Good point about the thermostats failing causing no regen on the E90. Are the F30 thermostats any better? We should have idea now the cars been out 5 years!