Another C5 mysterious expiry

[Richard Stevens]

After a few miles (in cold fog) of a longish journey 3 weeks ago, the engine (1.6HDI) cut out a few times when changing down on hilly roads. Restarted okay, decided to carry on, seemed okay as operating temps reached.
Later found a lack of power on the motorway, car wouldn't sustain 75mph in cruise control going up inclines. Next morning wouldn't start - at least, did start but died after a couple of seconds with a nasty tapping.
Got towed to a Citroen main dealer, and to cut a longer story short, they replaced the HP fuel pump, timing belt, pulley and water pump, plus a fuel pressure sensor. They said they also suspected fuel contamination. I have a sample, not tested yet.
Got the car back supposedly fixed (don't ask the cost!) after 5 days.
Seemed ok, but the next day after about 200 miles a tapping noise started but went away on occasion (which made me discount big-ends). Noise linked only to engine RPM. Gradually got louder. Had I been in the UK I would have stopped, but I tried to nurse it to the channel tunnel. It died 10 miles short of Calais. Car is now back at home, not worth repairing.
All this happened in France making the whole episode fairly nightmarish, not to say expensive.
The breakdown cover was excellent, but the nausea and waiting were a real pain.
I have since been told that the 1.6 engine is prone to big-end failures; my local garage now confides that they had the same problem in the summer on a Picasso. I have seen how the big-end bearing shells are free to rotate and so could run quietly during an extended failure. But what would be the cause in an engine only having done 75000?

Now I have to scrap the car/recoup what I can from it.

I have enjoyed my C5, and am looking at another, but the 2.0 diesel this time. One I have seen for sale claims to have a 138bhp 2 litre, SOHC 16 valve engine. It's on an 06 plate.
I thought the 16-valve engine was the DOHC type.
So, which diesel engine does NOT have a DPF?

Engine experts, advice please!

Good motoring
RS