2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode

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Mon 20 Nov 2017 21:07
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - Shane binding
Evening guys bit of a story to my issue, a few months ago I replaced the battery on my car then a few weeks later engine light came on took it to a mechanic who plugged it in and said dpf fault. So leave the car and had the dpf taken off and given an acid bath so it's clean, everything reset and away I go. Approx 700 miles later engine light comes back on, few days later limp mode. back to the garage and code read again and dpf issue. I have now had two of the sensors replaced and every time approx 700 miles and the same thing happens again. Now it's gone into limp mode I'm after advice from you guys?
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Mon 20 Nov 2017 21:17
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - RobJP

Probably needs a new DPF, the old one is too clogged to clear.

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Mon 20 Nov 2017 22:59
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - Shane binding

Probably needs a new DPF, the old one is too clogged to clear.

Really even though it was removed and had an acid bath?
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Mon 20 Nov 2017 23:24
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - RobJP

Really even though it was removed and had an acid bath?

I'm not sure (and I'm a scientist) exactly what cleaning a DPF out 'with an acid bath' is supposed to accomplish.

OK, lets start at the beginning - a 'new' DPF basically catches the soot from the engine that (on old diesels) would be pushed out of the exhaust pipe. Then, when the exhaust gets fully up to temperature, that soot gets burnt down to ash, which sits inside the 'body' of the DPF. (this is why lots of short trips are really bad for DPF diesel cars - the exhaust never gets up to temp, and the DPF gets clogged up with soot that hasn't burnt down to ash).

Eventually, even with a good system and lots of high temperatures, the DPF gets full of ash. That ash is basically inert. It will not react with acids or alkalis. So that's why I don't see how an 'acid bath' would help to clean it out.

The only way that I know of to 'clean out' a DPF that's like that is by a system which basically blasts very high temperature air (300+ C, I seem to recall) through the filter for several hours, basically vapourising the ash.

You can't 'clean' a clogged DPF with acid, or snake oil, or any of those 'magic' products. You either get it removed and cleaned properly, or you get it replaced.

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Tue 21 Nov 2017 01:01
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - EoinT Dub
Double check the hoses haven’t crumbled away. Happened my 2010 2.0tdci 140 two years ago and seems to be a common fault.
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Tue 21 Nov 2017 09:03
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - pd

Would echo the above comment. Always check the hoses first on a Mondeo Mk 4.

What is the code and what are the DPF pressure readings at idle? You should be able to tell if it is blocked from those. If it is reading zero or near zero the pipes have had it.

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Tue 21 Nov 2017 09:37
2.2 tdci mondeo tit x sport 2011 - Ref cars in limp mode - Railroad.

Best thing you can do is get rid of it and buy a petrol. If you're not doing above average annual mileage then a modern diesel with a DPF is not suited to you and will continue to give you expensive trouble.

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