Technical DPF Regens - how often?

[Bonefish Blues]

Does anyone have any data on how often their/other 1.3 Multijet does a DPF regen? Interested to know/compare - mine seems to be in the region of 170-200 miles or so, and I'm wondering if that's normal?
Similarly, how blocked does a DPF have to be in order to regen - and does a regen wholly unblock back to 0%, or does it get progressively more blocked with age, or what, exactly?
Oh, and how long do they take, on average?
Educate me in the dark art of DPFs & regens please. Yours, Regen Student

 

[lunchbeers]

Can't help with the 1.3 but I'd get approx 400mi out of my 2.4 Multijet, used to take about 15mins, you could tell when it was doing it as the exhaust would become boomy, the currrent mpg display would drop through the floor and the boost gauge wouldn't move, despite the car driving as normal.

I guess even though mine was a bigger engine, I assume the DPF was much larger too...I think with most of these things it's how they're driven and where.

Generally it'll always display a percentage, but worked out on pressure, I never looked at mine following a regen, but would be surprised if it went to 0% - I was under the impression MultiECUScan's quirk would be showing 30% clogged, but would actually mean 30% free (70% clogged).

As there is a market for replacements, I guess they either clog to the point they never regen, and effextively become scrap - shortly after buying mine, it threw on a light for DPF, mine got filled with cheap supermarket coke and lightly jet washed and was fine for the next 2 years.

Short distances between regens would suggest it's on its last legs or might benefit from a professional cleaning, either way a bit more investigation might be warranted.

 

[Bonefish Blues]

Thanks - that latter part is the subtext for my posting as it seems rather more frequent than I expected.

 

[lunchbeers]

What's your general drive like? Mixed, mainly motorways, or town driving?

Under the impression shorter trips and town will cause it to clog sooner as you're not seeing the requisite engine temps and activating the conditions for a regen, also they might not be completing, hence why they're common.

 

[Bonefish Blues]

10 mile trips 4x daily, incl 3 miles of 70mph dual on each, plus some pottering, various.

Decent profile. I think, and roughly 1000 miles pcm, perhaps a little less.

 

[lunchbeers]

Pretty strong, although your 70mph should trigger it, perhaps not far enough in 1 stretch... mine would need a decent (20mi or so) stretch at 2000+ rpm for a while to successfully trigger it, being a manual transmission, it was easy enough, once I could get a clear run on the motorway.

What's your mileage by the way? 1k a month is on the higher end nowadays - perhaps you've just reached the end of its useful life

 

[Bonefish Blues]

117K - but emissions are bob-on in the latest MOT a few weeks ago.

 

[Greasytrucker]

117K - but emissions are bob-on in the latest MOT a few weeks ago.

Doesn’t really tell you too much though as diesels only have a smoke test rather than emission test. A partly blocked DPF can quite easily pass

 

[The Panda Nut]

My MES did not show my Bravo doing regens, so I asked the Stealer to check. It had done something liek 860 that the dealer software could see. I suspect its all about how fast you drive and how often. The warning lights associated with this never lit up 10 100000 miles.

 

[lunchbeers]

117K - but emissions are bob-on in the latest MOT a few weeks ago.

Hardly over-the-hill then... if you have MES, maybe plug it in next time you notice it regen and see what value it reverts to.

 

[Bonefish Blues]

I haven't got it I'm afraid, so can't do it real-time

 

[Herts Hillhopper]

MES keeps a log. Mine seems to be every 200-250 miles or so. You have no idea it’s happening when driving.

I’ve never seen the warning light come on which suggests it regens long before it’s too late. I tend to end up with a long drive once every couple of weeks on average- 20 miles of fast road. But the rest is generally urban, or mixed county lane journeys. What it needs is a hot engine and fairly steady speed - and I seem to remember reading somewhere, over 2000 rpm (50mph or so in top) for about 15 minutes.

Basically, drive normally, but do make sure there’s a regular long run. Lots of round town journeys are not good for modern diesels.

 

[Bonefish Blues]

MES keeps a log. Mine seems to be every 200-250 miles or so. You have no idea it’s happening when driving.

I was chatting to a mechanic the other day and he confirmed that what I'd felt as a lack of the usual engine braking at the end of the dual carriageway was likely a regen cycle. I also get a puff of white smoke as the fuel is pumped in.

 

[Twotone2]

I've a 2014 Citroen Nemo 1.4 diesel van (basically a Fiat Fiorino I think) 55,000 miles it has just recently done a regen, first time I've ever noticed it but the led came on the dash with a message saying it was doing it's thing.

I drive about 4,000 miles a year and mainly urban but occasional motorway driving for about four or five miles at a time maybe once a week.

 

[Bonefish Blues]

I also don't get the dash light at any point

 

[Herts Hillhopper]

I also don't get the dash light at any point

You shouldn’t see the light come on If all is working correctly as it will regen automatically when it needs to and not tell you it’s happening.

(@Twotone2) The light only comes on if it’s not been able to regen by itself (too many short journeys) and lights up to say ‘take me for a run please’, or, if a regen was interrupted, when the next start up the light shows to say ‘go for another long drive’.

Diesels fitted with a DPF need frequent (weekly) long runs (at least 20 minutes of fast road with few gear changes) and really are not suited for low use, urban driving.

The filter can never ‘block’ as the system will always regen long before it’s full. It measures the pressure drop across the filter to decide when to try to clean itself (by burning off its contents). Only if (1) the car only ever does short runs, and (2) you ignore the warning light if it comes on, will the filter become over-filled.

 

[Bonefish Blues]

Any merit in chucking a bottle of one of the dpf cleaning solutions into the tank every so often?

 

[Herts Hillhopper]

Any merit in chucking a bottle of one of the dpf cleaning solutions into the tank every so often?

No. The system cleans itself by running the exhaust at an elevated temperature and injecting a little fuel into the exhaust stroke to burn off. Regular diesel works just fine - that’s what the system was designed to use. Ignore the hype and marketing aimed at those who might succumb, and just drive it normally. But not all little short runs

 

[Herts Hillhopper]

As a little postscript to this, read my comment from another thread about DPF regens. This was in answer to a question about occasional puff of white smoke under acceleration but explains more fully how the DOF will always try to keep itself clear:

https://www.fiatforum.com/threads/embarrassing-q-where-is-my.503726/post-4706632