Hi Just joined this forum in a bid for help,I have a 2005 L200, k64. When its idling the revs fluctuate between 850 and about 600 making the engine shake quite bad, from idle when i touch the throttle it jumps to 1400/1500 rpm for about 30 seconds then drop to 600 rpm and nearly stalls and returns to the rough idle. Also when in 5th gear at about 2200 rpm it sounds like a bit of a misfire causing a small vibration, but when i accelerate through to 2400 rpm it runs fine from there, the problem seems to be in the lower rev range. Took it to a garage and there were no fault codes appearing. There is a little black smoke at the high end when i rev it up, the pick up has only covered 92000 miles, thanks in advance for any help……

Start simple , try fuel filter and a can of Forte deisel cleaner