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chicaneuk

Tackling a blocked DPF.. (520d)

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45 minutes ago, chicaneuk said:

apparently the DPF has 50g+ of soot in it... which I believe is also a lot!

 

Take those metrics with a pinch of salt. They are just estimates based on back pressure. Did it say 50g of soot or ash? I'm surprised it doesn't say a lot more for soot given your back-pressures. Maybe it just tops out at 50g. Normally the soot reading goes to about 40-50g from zero, then it decides it needs a regen and when comp;ete it drops back to zero. Ash is a by-product of regens and builds very slowly (estimated again) over the life of the car. It goes up by 0.2g or something after each regen, so 50g would be a normal reading for it.

 

Keliuss

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That was the soot value ... Ash I don't recall seeing .. maybe said 6-7g of ash but I wasn't watching it as a live value unfortunately so don't observe it go up.

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Have just ordered a Dremmel with a metal cutting tool and a new set of bolts / gaskets as, from the sound of things, the bolts on the DPF tend to put up a bit of a fight :| I've also got a reciprocating saw if I need to get  bit more hardcore.

Edited by chicaneuk

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3 hours ago, chicaneuk said:

That was the soot value ... Ash I don't recall seeing .. maybe said 6-7g of ash but I wasn't watching it as a live value unfortunately so don't observe it go up.

 

I guess it tops out then at 50g. You won't see the ash value change. Best of luck with cleaning it out :). I assume you'll report back with your findings.

 

Keliuss

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17 hours ago, Keliuss said:

 

I guess it tops out then at 50g. You won't see the ash value change. Best of luck with cleaning it out :). I assume you'll report back with your findings.

 

Keliuss

 

Absolutely.. my pet hate are forum posts where someone gets a load of advice to tackle an issue and then vanishes with no updates!

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Well the first mystery ... and I haven't even started properly yet! Jacked the car up this evening in preparation for starting work on it in the morning and was confused to see that when peering down into the engine bay and when scrambling and looking up underneath it, I assumed the DPF was right there straight down out the back of the turbo given that I can see the pipe leading down there to the pressure sensor but seemingly not? Is that the catalytic converter? So am I being stupid and the DPF is a little further back along the exhaust system? According to build dates and RealOEM I should have this unit on mine (see attached).

 

I'm not a total newbie working on cars.. I've done a few jobs over the years but must confess to having never really done much with the exhaust system let alone DPF's and catalysts!

 

 

Screenshot 2021-04-21 at 20.34.17.png

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I only really know about 6 cylinder BMWs but in those there was a separate DPF before 2007 but the LCi models have a combined DPF and Cat. The first half of the unit is the cat and the second half the DPF. You can still wash it out.

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There is a lot of confusion around this and I don't have any personal experience answer, but here's my two cents. RealOEM is not infallible for a start. I think part of the confusion is due to LHD and RHD cars having a different setup and perhaps E60 and E90, E87 etc with N47 adding to confusion when people do have experience of those.

I believe the RHD LCI models have a separate DPF unit further back and that @JasonH is likely correct, but for LHD cars. Realoem gives part numbers for a diesel catalyst on one page and a separate number for the DPF on another. There is also a page with the combined cat/DPF but it's greyed out for my RHD LCI car.

 

Also, my "pre-DPF pressure sensor" pipe phisycally goes down beyond the first box suggesting the first box is cat only.

 

Keliuss

Edited by Keliuss

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OK.. well I will eyeball further down the exhaust system otherwise I guess it’s the first box coming off as it looks the same as from various videos on YouTube etc and seems to suggest it’s a cat and dpf combined. 
 

But as you say @Keliuss the pressure sensor pipe goes down past this first ‘unit’ so one would assume the DPF is further along. 
 

My faith in RealOEM is now rather shaken though! :-) 

Edited by chicaneuk

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OK well some good news and some bad news. Confirmed the location of the DPF as per the picture a bit further down the system so RealOEM speaks the truth! Problem is every single bolt is not only completely rusted and rounded to oblivion but the ones on the top are of course completely inaccessible. I then realised it might be easier to drop the entire rear half of the exhaust system so I could tackle the nuts with the dremel from all angles.. but the clamp just by the flexi is also of course a completely corroded nightmare and unfortunately I simply don't have the spare time (or honestly the confidence) to get so deep into the problem. If I wasn't now a dad with zero spare time and didn't depend on the car I'd be happy to just get it up on some axle stands and chip away at it for a few weeks but honestly I just need the car working :(

 

So for now it's back to plan B which is brim the tank, add some DPF cleaner additive, and take it up and down the M6 for a few hours clearing the codes on Carly and hoping I can force a regen. Otherwise it's going to have to go into the garage for the work and whatever hideous bill that will entail :(

Edited by chicaneuk

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Best of luck with it. Don't bother with the "high revs, low gear" or "over 70mph" advice. Just drive it as normal. I've been watching mine regen on an app for over 2 years and the best regen conditions are a nice steady speed in the 60-70 mph range for 20-30 mins. If you can get it to regen, pay no attention if your soot value drops back down under 10g. It is a good sign of course but not accurate at all. It seems the software just drops it back slowly so long as the regen temps are above 400C or so. As you say, just try requesting regens if you get that far and see if the back-pressure readings eventually come back down. Also, during a regen the pressure will be much higher than usual due to the higher temps.

 

Keliuss

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Thanks for that Keliuss. Well sadly no joy on my first outing.. coolant temperature good, full tank of diesel, exhaust gas temperatures fairly hot but despite repeatedly trying to clear codes and request a regen, it never seemed to want to initiate one. Seemed to variously keep coming back with the same codes:

 

00481A - Particulate filter system

004530 - Boost pressure control, control deviation

004D00 - Exhaust back pressure sensor, signal

 

The back pressure one I keep telling myself is because of the high readings it's getting as I've got two back pressure sensors and swapped them over mid drive, with no change though I would say that the frequency of the error after swapping did seem to be less often...?!

 

Back pressure under any kind of throttle would still keep climing up to just short of nearly 2000 hPa and soot level remained constantly at just under 50g. I did knock it down into 5th and cruised between 60-70mph where possible.. though the M6 was astonishingly busy.. but should have had ample time to start a regen.

 

So I guess I just need to keep taking it for long steady drives whenever I get some free time in the coming days / weeks and just hope the DPF cleaner additive breaks down the blockage enough to get the back pressure values back into some sensible level where the regen might actually initiate?

 

Naturally the boost pressure control alert is concerning as this doesn't really help matters concerning lack of power and flat feeling motor.. is my problem specifically being caused by the DPF or now this fault code?! Arrgh.

 

One ray of hope though.. my neighbour who is extremely handy with the spanners saw me working on the car earlier and after a chat has offered to give me a hand as he has all the tools (and knowledge) to get the rusty bolts, etc off. The only thing he said was that he'd want to make sure we had all the nuts and bolts we might possibly need before starting.. so in theory all I'd need is that clamp by the downpipe, and a new set of bolts and gaskets for the DPF (which I have) and we should be good to go to basically drop the entire post-cat section of the exhaust and get the damn DPF removed and cleaned?

Edited by chicaneuk

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Yes drop the whole exhaust off. It's surprising easy but it is heavy. Impossible without. I've tried both removing the exhaust and trying to remove the DPF without... 

Edited by JasonH

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Yes agreed - drop the entire exhaust from wherever you can separate it and drag it out the back.

I had to do that the first time and cut off all the DPF bolts. Once you've been in there it'll come off really easy the next time if, like me, you have to wash it out 4 times before admitting defeat and smashing the material out completely.

Edited by roi354

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Cheers guys.. think this is the route I'm going to take. Going to order a replacement v-band clamp and the bracket (30 quid!! FFS!) for by the flexi so wherever we end up seperating it, we should be covered.

 

If needs be I'm going to take a punt on an eBay £150 DPF as I don't really want to go down the route of smashing out the innards and mapping it out just in case an MOT tester gets smart.

 

*Edit*
 

Found a very well reviewed professional DPF cleaning company based about 20 minutes away. Neighbour has confirmed he is happy to help so maybe next weekend we will work to get the exhaust system off and separate the DPF and I will go see about getting it professionally cleaned out (wasn’t too happy about chemicals and diesel particulate going down the drain here!) and then reinstall with new bolts and gaskets hopefully a few days later.

 

As always will keep the thread updated. 

Edited by chicaneuk

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So finally an update! I hadn't forgotten.. just hadn't had any time to look at this. With the help of the neighbour, we got the car up and cut off the bracket (number 3 in the diagram further up the page) as the nut was just a crusty nightmare. We then loosened all the hangers, etc and were able to drop the exhaust and then gradually drag it off the flexi and out from under the car. Success! Neighbour then took the angle grinder to what was left of the nuts and bolts holding the DPF into the exhaust system and seperated with a hammer and screwdriver. Hurrah! All in all took about an hour and a half.

 

I was all set to throw the DPF into the other car to take up to the specialist in Wolverhampton, to drop it off for a clean.. but went down to the garage at the side of the house and as I was doing so, noticed a van pull up outside the house.. I assumed it was an amazon delivery I was waiting for, but no.. two grotty bastards grabbed my DPF and drove off. I walked up to the drive, looked where it was originally, looked at the van vanishing down the road, and realised they'd stolen it.

 

Unbelievable. Have just had to fork out for an affordable aftermarket alternative from Euro Car Parts for £260'ish as BMW wanted nearly £1700 (!) for a new one.. :|

 

Updates to follow when the new DPF comes and we can get it back on the car. Honestly, what a day. Thrilled at the successful removal of the old one then just shock and anger at the old one getting stolen from right under my nose!

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Thieving scum :-x they want there fxxking hands chopping off.

I know it won't make you feel any better but I had a similar thing happen to me seven years ago.

Car jacked up on driveway for two days while I did work on it, I came home from work the second day & wondered why the exhaust was on the floor under the car :unsure:

Yep they'd cut the cat out bxxtards & another time my exhaust was off the car

infront of the car on my driveway next to the garage door (not visible from the road)

& that got pinched by scrapmen.

A duel turbo back full system!!!

 

I hope you have more luck with the replacement.

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Thanks mate.. and sorry to hear that you've been a victim of this too. It's just so inconvenient now as at least I had a genuine BMW DPF to get cleaned and refitted but now I've had to go aftermarket.. so god knows how good the quality / longevity will be.

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Idiots likely thought it was a cat. Had my E34 one stolen/cut off before Xmas. Bastards. Needed a new entire exhaust system. 

 

Keliuss 

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1 hour ago, Keliuss said:

Idiots likely thought it was a cat. Had my E34 one stolen/cut off before Xmas. Bastards. Needed a new entire exhaust system. 

 

Keliuss 

 

Does an E34 even have a catalytic converter?!

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2 hours ago, chicaneuk said:

 

Does an E34 even have a catalytic converter?!

 

From 91' onwards I think. Or thereabouts. Worth about £400 in scrap apparently.

 

Keliuss

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18 minutes ago, Keliuss said:

 

From 91' onwards I think. Or thereabouts. Worth about £400 in scrap apparently.

 

Keliuss

 

I was told that even a dirty choked up DPF still has a 'weigh in' value of about £200 so still worth stealing.

 

Anyway... my replacement DPF from Euro Car Parts is getting delivered later today so hopefully we can get the car back together in the next few days, all being well. As always, will keep the thread updated.

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5 hours ago, chicaneuk said:

 

I was told that even a dirty choked up DPF still has a 'weigh in' value of about £200 so still worth stealing.

 

Anyway... my replacement DPF from Euro Car Parts is getting delivered later today so hopefully we can get the car back together in the next few days, all being well. As always, will keep the thread updated.

 

I'd have my doubts about that. DPFs are ceramic, usually silicon carbide which isn't terribly valuable. Cats have palladium, platinum and rhodium in them. If DPFs were worth £200 in scrap we'd be plagued with thefts and you'd hear a lot more about it.

 

Keliuss

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4 hours ago, Keliuss said:

 

I'd have my doubts about that. DPFs are ceramic, usually silicon carbide which isn't terribly valuable. Cats have palladium, platinum and rhodium in them. If DPFs were worth £200 in scrap we'd be plagued with thefts and you'd hear a lot more about it.

 

DPF's also have rare metals just less than cats. I just sold my removed DPF from E53 3.0d for 100€ to recycling company. My friend had 110€ for his E61 LCI 530d DPF, just DPF taken out of the housing and cat left alone.

 

https://katmetal.fi/catalyst-recycling/

.

Edited by Clavurion

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41 minutes ago, Clavurion said:

 

DPF's also have rare metals just less than cats. I just sold my removed DPF from E53 3.0d for 100€ to recycling company. My friend had 110€ for his E61 LCI 530d DPF, just DPF taken out of the housing and cat left alone.

 

https://katmetal.fi/catalyst-recycling/

.

 

Ah crap! Well, when all the low hanging big fruit has been picked they will simply move on to the smaller fruit higher up the tree. It's a huge problem:

 https://www.rte.ie/news/2021/0422/1211517-catalytic-converter-seizure/?fbclid=IwAR21kZcjWVADitFnKeZZsE1aJ--kLio_zQeyoa_8sQOsuVuZfifelcjqdyQ

 

Keliuss

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