Dpf cleaning or buying

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So i ran the van for an hour in 3rd gear at about 50mph on the dual carriageway. I had added to dpf cleaner x 2 in the fuel tank a few days before.

Just been down for the retest and it was still at 1.5 approx. But they put it through which was nice of them.

So the system has a problem. Do you think i should get the dpf cleaned with acid ? What else could it be ?
 
So i ran the van for an hour in 3rd gear at about 50mph on the dual carriageway. I had added to dpf cleaner x 2 in the fuel tank a few days before.

Just been down for the retest and it was still at 1.5 approx. But they put it through which was nice of them.

So the system has a problem. Do you think i should get the dpf cleaned with acid ? What else could it be ?
Just put it out of your head until next year and as already said, scratch the plate out before you take it for test. ;)
 
Prepare a few weeks in advance next year, oil change, air filter, can of forte and a good run.
Wont hurt to use the Forte treatment every 6 months.
 
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Thought I had planned this time but will try the forte stuff as well.

I’m going to get a diagnostic on the filter to see where it’s at with soot etc.
 
Some good recommendations re. Forte products. Never used before, only the Redex diesel cleaner fuel additive.

I'm a big fan of the "drive it like you stole it"/Italian tune up just before MOT emissions tests. My 2004 Scudo has the HDI engine, and mercifully the only emissions controls on it are the EGR and cat - vehicle design was before DPFs, Adblue, etc. I normally drive like a maiden aunt on her way to church - but MOT day is different, the one day of the year it gets a bit of abuse. Making sure the engine is fully warmed up first, I start by driving locally, pulling away with foot flat to the floor in first which initially gives few clouds of black smoke. Give it a bit of a rant through the gears before taking it for a burn up on the motorway - 70/80 mph in 4th gear. Afterwards any standing starts flooring it in first are free of any smoke - so it's done the trick. Then straight in for MOT, staying with van and keep engine running until they take it in for test. My readings are always approx half what the limit is, which isn't bad for such an old van with 108,000 on the clock.

Some mention scratching something off a plate in this thread? What plate? What detail is being scratched off? What does it achieve? Just interested out of curiosity as never heard of this before.
 
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Some good recommendations re. Forte products. Never used before, only the Redex diesel cleaner fuel additive.

I'm a big fan of the "drive it like you stole it"/Italian tune up just before MOT emissions tests. My 2004 Scudo has the HDI engine, and mercifully the only emissions controls on it are the EGR and cat - vehicle design was before DPFs, Adblue, etc. I normally drive like a maiden aunt on her way to church - but MOT day is different, the one day of the year it gets a bit of abuse. Making sure the engine is fully warmed up first, I start by driving locally, pulling away with foot flat to the floor in first which initially gives few clouds of black smoke. Give it a bit of a rant through the gears before taking it for a burn up on the motorway - 70/80 mph in 4th gear. Afterwards any standing starts flooring it in first are free of any smoke - so it's done the trick. Then straight in for MOT, staying with van and keep engine running until they take it in for test. My readings are always approx half what the limit is, which isn't bad for such an old van with 108,000 on the clock.

Some mention scratching something off a plate in this thread? What plate? What detail is being scratched off? What does it achieve? Just interested out of curiosity as never heard of this before.
There's usually a number in the corner of the compliance plate (or label) (sometimes with a "-1" superscript after it. That's the MOT smoke limit for the car. If that is illegible for any reason, DVSA's instruction to the tester, is to just test to the default smoke limit (which is nearly always less demanding). Really, they ought to just make an illegible plate a fail.
 
I use Forte, there's one called "Diesel emissions reducer" which is specifically designed for the MOT - chuck it in a quarter tank before the "extended test drive" (as printed on the bottle). I always do an oil and filter change as well. Made my last two fails into passes and this year got a "fast pass' as I did it before the test.

My tester said the "Italian tune up" things is more about getting the cat/DPF etc absolutely "red hot" so it's as effective as it can be.

Mine are pre 2010, I think euro 4 and don't even have DPF's and achieve 0.9 with a bit of help so I suspect there's something wrong with your car and agree about a diagnostic check.

This is the sticker (bottom of passenger B pillar on VW). The limit is the number in the sideways box in the bottom right hand corner. I keep meaning to scratch it out but I've heard it's now on the MOT database - but clearly as per Trevor there's a way to override it even if it is.
 

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I think the italian tune up can also make things worse due to more soot but maybe thats just an old wives tale.
The correct procedure is to drive it with the revs raised slightly for longer periods as suggested earlier in the thread.
 
I use Forte, there's one called "Diesel emissions reducer" which is specifically designed for the MOT - chuck it in a quarter tank before the "extended test drive" (as printed on the bottle). I always do an oil and filter change as well. Made my last two fails into passes and this year got a "fast pass' as I did it before the test.

My tester said the "Italian tune up" things is more about getting the cat/DPF etc absolutely "red hot" so it's as effective as it can be.

Mine are pre 2010, I think euro 4 and don't even have DPF's and achieve 0.9 with a bit of help so I suspect there's something wrong with your car and agree about a diagnostic check.

This is the sticker (bottom of passenger B pillar on VW). The limit is the number in the sideways box in the bottom right hand corner. I keep meaning to scratch it out but I've heard it's now on the MOT database - but clearly as per Trevor there's a way to override it even if it is.
I will look at the forte products next time.

Ive done everything you need to do - changeoil and filter, add the cleaners, take it for 1h driving before in 3rd gear and not switch off at the mot centre. Still got the same rate i did on the first day, so a fail.

If you are getting 0.9 i think that might be a fail for me as its 0.7 you need.

If you dont have the DPF then that maybe why you get through ok.
 
There's usually a number in the corner of the compliance plate (or label) (sometimes with a "-1" superscript after it. That's the MOT smoke limit for the car. If that is illegible for any reason, DVSA's instruction to the tester, is to just test to the default smoke limit (which is nearly always less demanding). Really, they ought to just make an illegible plate a fail.

Thanks to everyone who gave info re. compliance label. Will look and see if I can find mine. Won't be defacing it though, as I'm not getting and problems at test time. Though, being an Italian vehicle of a certain age (at least the badges are Italian), any labels may well be in Roman numerals.

Seeing the potential problems others have with more modern vehicles, I'm not looking forward to the day when I have to downgrade to something newer.
 
Does the van still have it's original exhaust, Trevor - including the catalytic converter?
John :)
In 2021 i hit a rock at 20mph. Thought it wasnt that big. It took out the whole under carriage and oil sump. So i had a lot of parts replaced under there.

Reading my receipt now it says the rear exhaust was replaced, interm exhaust pipe, particle filter exch, particle filter clamp, inlet pressure pipe, plus lots of clamps and other bits, but nothing more talking about the exhaust system.

I also had a whole new engine fitted after this repair as on leaving the garage the engine almost blew up. It turned out they had missed the fact the engine had been running with no oil in it.

So i have a new engine which has done 50k miles since it was replaced. Same for the exhaust system.
 
I've only mentioned this because in the past I've fitted pattern cats and DPF's - neither of which worked well as the original equipment.
This was to the Berlingo also, purely a coincidence though I think.
John :)
 
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