Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked

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Thu 14 Feb 2013 15:33
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - silverarrow

Following a visit to the dealer afrer experiencing limp mode and the yellow engine light came on the dealer replaced an actuator motor for the intake shut off at a cost in excess of £500. The dealer reported that a test had revealed that the diesel particulates filter was 200% blocked with soot and was not cleaning itself and need replacement at a cost in excess of £2500. I should add that the limp mode and warning light has been a constant problem since the car was in warranty but not at the same time. The light disappeared after a few runs and the limp mode after every restart, The sealer replaced a crankshaft sensor under warranty to cure the problem which it did temporarily.

Does anyone have any similar experiences with the 320 cdi engine and can anyone suggest a cheaper course of action

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Thu 14 Feb 2013 16:04
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - wemyss

There are two adverts on this page to remove them. No doubt someone will come along with experience or knowledge on this subject.

wemyss

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Thu 14 Feb 2013 19:39
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - Collos25

Take the car to a Mercedes specialist not a main agent and see what they say,The DPF can easily be cleaned and the 2500 for new one is a joke if you shoparound you can buy a new one at a much cheaper price .

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Fri 15 Feb 2013 08:54
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - skidpan

200% blocked, how does that work. 100% is the maximum figure that can be achieved. Garage are having a laugh.

If the DPF is blocked a forced regen on the diagnostic tester may possibly clear it but probably not. Once blocked beyond a certain level it is not possible to recover one. Jet washing and other urban myths will not work so don't waste your money. To remove the soot they need to be heated to 600 degrees and no jet wash I know can do that.

DPF's are widely available now so no need to go to a main dealer.

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Fri 15 Feb 2013 09:02
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - MrEckerslikefromRamsbottom

I agree -- As soon as he said "200% blocked", just turn away and go elsewhere!

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Fri 15 Feb 2013 10:15
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - Collos25

"Once blocked beyond a certain level it is not possible to recover one"

Not quite true there are firms with TUV approval all over Germany that will clear any DPF and give a gaurantee of the work ,this service is not cheap but a darn sight cheaper than buying a new DPF.

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Fri 15 Feb 2013 10:29
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - skidpan

"Once blocked beyond a certain level it is not possible to recover one"

Not quite true there are firms with TUV approval all over Germany that will clear any DPF and give a gaurantee of the work ,this service is not cheap but a darn sight cheaper than buying a new DPF.

Talked to a chap late last year who had recently invested in kit to recover HGV DPF's. Basically they are put into a chamber, heated to 600 degrees and then have compressed air blown through, takes about 12 hours for the heat up, "regen" and cool down. He did not think it would be cost effective and did not know if would work for car DPF's but was willing to try if anyone was willing to pay.

He was dismissive of all those companies robbing people by pretending to jet wash the soot out, he mentioned one that soaked the DPF with petrol and then put it in a bonfire. As he says they are breaking environmental laws by allowing toxic water into the public sewers.

I agree, such companies need prosecuting.

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Fri 15 Feb 2013 11:42
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - craig-pd130

Basically they are put into a chamber, heated to 600 degrees and then have compressed air blown through, takes about 12 hours for the heat up, "regen" and cool down.

That's a good idea, and would 'coke' the soot within the heat limits that the DPF canister and matrix should be designed to withstand. I wonder what that service would be priced at?

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Fri 15 Feb 2013 12:04
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - unthrottled

Are we dealing with soot or ash? Soot can be burned off or washed out with a solvent.

Ash is a different matter. It isn't combustible or soluble.

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Fri 15 Feb 2013 12:34
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - galileo

If soot is composed of carbon i thought it was insoluble in anything but hot concentrated mineral acids, which I guess would also dissolve the filter casing?

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Fri 15 Feb 2013 13:52
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - unthrottled

Know why diesel engine oil is black? It's got soot held in suspension :)

OK, ok ,held in suspension isn't physically the same as dissolved.

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Fri 15 Feb 2013 14:22
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - TeeCee

As he says they are breaking environmental laws by allowing toxic water into the public sewers.

I'd love to know how that differs from having it burned off out of the tailpipe and then washed out of the sky and into the public sewers come the next rain.

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Fri 15 Feb 2013 15:13
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - craig-pd130

the regeneration process converts the soot into carbon dioxide and water, and leaves any residue trapped in the DPF.

The ash takes up much less volume than the soot, though, so the DPF should normally last the service lifetime of the vehicle.

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Sat 16 Feb 2013 08:40
Mercedes S Class 320 CDI 2009 99000 miles - Diesel Particulates Filter blocked - injection doc

"Does anyone have any similar experiences with the 320 cdi engine and can anyone suggest a cheaper course of action"

Yeah wash them out backwards with a jet washer, to be honest very little comes out !I'm sure a train or a plane plane puts out far more polution in 2 minuets than washing a DPF.

I washed out a merc 220cdi one the other day & the Garage was astonished at how little soot came out but restored the cars performance.

Must make sure a merc is running on low ash oil ! otherwise the DPF's will soot up !

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