Evening everyone

just got home after being recovered by AA (this time very good service and under 2hrs from 1st call to back of truck!)

So I have major problem and would be useful to know if anybody else had similar

The Car:
A6 Allroad 4B C5 AKE 2.5TDi 2003 with 180k. (cam belt at 150k - fuel filter - Steering Pump - Alternator approx 8k ago)

Scenario:
Car been running well with no 'mechanical' issues for a good while. Then today, cruising on M25 at a full 70mph/Half Throttle (a rare bonus on M25) and in lane 3 overtaking lane 2 .....with nothing in lane 1!!!!!!!!!!! when I just felt something different - either engine note or small vibration or both. I am very mechanically sympathetic and generally notice if something 'different' straight away!

I was 1 mile from Clackett Lane, so pulled over to come off at Services and noticed lack of response from throttle/lack of power. Stopped at Services with engine running and it was Lumpy as **** on Idle. Not Rattling - apart from Idling on 4 or 5 cylinders and No Smoke. And cant do much about it there, so decided if was running would try get back home rather than get stuck at Clackett Lane!!.

Pulling back onto M25 was a mission as had no power at all, but got up to 50mph and decided that was sufficient. carried on at 50 to M26 and was fine until came to incline where speed dropped to 40-35 followed by some smoke for a short while (dark but not black) by time had done another 5 miles to next junction engine had zero power and if I gave any throttle was smoking again - but would idle at NORMAL revs although still Lumpy as ****. Had to queue at roundabout but managed to get to layby just the otherside by just letting car drive itself on tickover.

Engine stills starts 1st time
Lumpy tick Over but still idles at 800rpm
Revs up slowly and after a moment rattles and smokes a bit (not LOTS)

.......... 25 Miles/35mins before this problem occurred, I had filled up with 58 litres of Shell 'normal' Diesel at Cobham Services. ( I only EVER use Shell Diesel now after having many issues with a previous car on supermarket fuels.........)

NO ENGINE MANAGEMENT LIGHTS ON CAR.... NO LIMP MODE NOTHING! ALL NORMAL.

I will get Diagnostic tool on car in next few days, as I suspect Injectors are going down 1 by 1?

I may be wrong... that's why any of your previous experiences would be good to know ????