DPF, long trip tomorrow

[s5tuart]

Even though I only usually do short trips in the 2016 CLS 350d I'm due a 2 hour return non-stop run tomorrow to attend a funeral.
I'm presuming that the DPF might benefit from a regen but I can't find in the manual if I can force this or if the car will only do it when needed.
My question is how do I know it's happening, if indeed it does at all?
Is there any dashboard sign that it's in progress or do I have to rely on experiencing higher revs/lower gear whilst on the motorway.
I always use VPower...is that keeping it clean enough to not warrant a regen?
Thanks

 

[Wighty]

Even though I only usually do short trips in the 2016 CLS 350d I'm due a 2 hour return non-stop run tomorrow to attend a funeral.
I'm presuming that the DPF might benefit from a regen but I can't find in the manual if I can force this or if the car will only do it when needed.
My question is how do I know it's happening, if indeed it does at all?
Is there any dashboard sign that it's in progress or do I have to rely on experiencing higher revs/lower gear whilst on the motorway.
I always use VPower...is that keeping it clean enough to not warrant a regen?
Thanks

You won’t notice on the motorway buddy (as far as I understand ) . The run will sort the car out nicely after all the short trips . You could when the car is hot and on the move drop a couple of gears and leave it on cruise control so that the revs are much higher for 20 mins . At least that’s what I do sometimes .
Don’t do what I did a couple of years ago , dropped a couple of gears so the revs sat quite high and then forgot about it for a couple of hours on the motorway at night

 

[rorywquin]

I'm sure contradiction will follow. However since switching my wife's car to BP Ultimate / V-Power diesel we have no regen events. She mainly does short trips and before using premium fuel it was a regular occurrence (that rattling noise). We get no indication that regen is happening or progress status (B Class).

 

[malcolm E53 AMG]

Always worth knowing when a DPF regeneration is occurring IMO but unfortunately manufacturers don’t share this view. It’s quite obvious when the DPF regen cycle kicks in on my OM642 engine, the revs rise by 300rpm, the exhaust note sounds sharper (a lot nicer IMO) and the car holds a lower gear for longer. I very much doubt whether any of these indications will be noticeable when cruising at motorway speeds.

I don’t use supermarket fuels and only fill up with standard 95 RON and the car runs exactly as it should, starts on the button and performance seems fine. I’m not doing any long journeys due to the pandemic but generally extend a journey if a DPF regen starts I’m not a big fan of not letting the regen finish it’s cycle.

I’m already running one petrol car and when I next change the estate it will be for petrol I just don’t do the miles nowadays although I’ll miss the low down torque characteristics of the diesel it’s perfect for modern driving

 

[ajlsl600]

Makers decided u dont need to know whats going on with yr car .some have found the relay involved and organised a light to come on. Some pimpled teenager fresh out of design school has decided that a dash message is more info than we need. Regen in process try to keep above 2000 rpm. Wud be nice.

 

[s5tuart]

Thanks everyone!
Mine is the OM642 with the 9G box.
I have noticed that at times the car holds a lower gear/higher revs but it doesn't ever last more than a couple of minutes, 5 at the most.
Trouble is the thing is so quiet that it's difficult to know what's going on without eyeballing the dash ALL the time.

 

[John Laidlaw]

As above, holding revs is an indicator a regen is 'in process', also a bit louder. BMW lead me to believe if mine has an interrupted regen it will start up again on the next time the engine is running. I think that's fairy dust personally so once a week I make sure I do a nice spirited 20 minute motorway hoon to make sure all is as it should be. Also checking the oil level isn't too high (therefore indicating dilution due to incomplete regens and diesel dump). I did get bimmerlink and the accompanying leads to check regen history and force if needs be but I got bored and haven't bothered yet!

 

[s5tuart]

As above, holding revs is an indicator a regen is 'in process', also a bit louder. BMW lead me to believe if mine has an interrupted regen it will start up again on the next time the engine is running. I think that's fairy dust personally so once a week I make sure I do a nice spirited 20 minute motorway hoon to make sure all is as it should be. Also checking the oil level isn't too high (therefore indicating dilution due to incomplete regens and diesel dump). I did get bimmerlink and the accompanying leads to check regen history and force if needs be but I got bored and haven't bothered yet!

Hmmm! I wish the Mercedes Me app would do that!

so can a regen start and finish in 5 minutes or less?

 

[Jim2]

Thanks everyone!
Mine is the OM642 with the 9G box.
I have noticed that at times the car holds a lower gear/higher revs but it doesn't ever last more than a couple of minutes, 5 at the most.
Trouble is the thing is so quiet that it's difficult to know what's going on without eyeballing the dash ALL the time.

It will all depend time wise on how "Clogged" it is, higher amounts of "soot" will take longer to clear. Most drivers will know their MB's inside out, and Malcolm10 and John Laoidlaw has mentioned here already, higher revs lower gear selection will generally indicate when a regen is taking place. For most drivers, they will be completely unaware that a regen is taking place ever, That is until a DPF warning light shows. Its madness indeed not to include a warning icon to show when a regen is taking place,but there is a DIY method to install a warning light....it involves taking connection from either the drivers side mirror or the rear window heater cable. Both come "alive" during a regen, so a live feed from either to a small LED will show when its regenning. Do a search here on the forum, and I'm sure that you will find the links on how its done.

 

[ajlsl600]

Anyone seen link.?

 

[Gazwould]

Supermarket derv from the same premium con refinery and add for a fraction of the price .

 

[sonic]

I have a 212 E350CDI, as others have said the exhaust note changes to a much nicer sound when in regen. It idles at least 300rpm higher, & higher revs before change up. At 70mph on the motorway it stays in 6th on my 7G box.
You should notice it on the motorway, & you certainly will off the motorway.

 

[Jim2]

Anyone seen link.?

I'll see if I can find it for you ajlsl600. Standby..

 

[John Laidlaw]

Hmmm! I wish the Mercedes Me app would do that!

so can a regen start and finish in 5 minutes or less?

Hi Stuart- well it's not exactly like Mercedes Me, more of a diagnostic kit which you drive via your iphone or Android device. It can force a stationary regen (just make sure there's no combustible material below the car!), and also give the history of successful regens/recent. As I say, been too lazy to use it thus far !
I understand 10 minutes is what an active regen takes, might vary from car to car....
Your long motorway journey might well result in a passive regen happening

 

[Botus]

the idea is to start a bonfire in the DPF (its kicked off and maintained by flooding with excess fuel... as an when the DPF signals there enough filth there to make it worth trying). In the old days a badly clogged one needs at least 20 mins uninterrupted at sustained motorway speeds.

Merc have been through a good few ideas to get this right maybe the do more frequently for short time... as very few ever do 3k rpm and 30 mins uninterrupted every week like they need

warm it up thoroughly >10 miles, then thrash the living daylights out of it to get everything really hot and drive 2 gears lower for 30 mins

 

[sonic]

Hi Stuart- well it's not exactly like Mercedes Me, more of a diagnostic kit which you drive via your iphone or Android device. It can force a stationary regen (just make sure there's no combustible material below the car!), and also give the history of successful regens/recent. As I say, been too lazy to use it thus far !
I understand 10 minutes is what an active regen takes, might vary from car to car....
Your long motorway journey might well result in a passive regen happening

If you stop & get out of the car during a regen you will smell the heat.

 

[s5tuart]

warm it up thoroughly >10 miles, then thrash the living daylights out of it to get everything really hot and drive 2 gears lower for 30 mins

Now that sounds like a grand idea

 

[John Laidlaw]

If you stop & get out of the car during a regen you will smell the heat.

You certainly will! and in the case of the A6 Avant I had you could literally see it as well! (Actually could be seen from space)

 

[John Laidlaw]

Now that sounds like a grand idea

win, win really

 

[Jim2]

Anyone seen link.?

Ok ajlsl600, tracked it down. Its from our sister forum Mercedes Benz Club. It a post from "Install Regen warning light" by mcgreedy, and begins at post Nr 40, It's very informative, with explicit step by step instructions on installing the light. Good Luck, if you decide to install it.