Mine failed emissions on it's first mot last week at 2.02 best . This week had a new air filter , 1/4 tank of fuel plus 60mls of Rhino (it's run on 70mls per full tank normally/standard diesel) then driven around at the weekend using 2nd,3rd gears at 4000rpm to use the fuel. Filled with standard diesel ready for it's re-test . Engine was oil changed/filter at 46,600 miles and now shows 51,600 miles .
SO-- yesterday after new air filter it was retested showing 2.27 , so took it away for a blast at high rev's locally then tried again which showed 1.96 best . Then went off for a 70 mile run at '' high rev's '' before another retest --- it was marginally better at 1.91 best .
I never see smoke while driving but of course the cars rear window is quite high BUT on flat accellerating for the test , it shows black smoke .
The key point for mine of course , is it was registered after the new rules date of 1st July 2008 , so has to pass less than 1.5 emissions.
I really don't want to throw away the cost of it's egr/dpf and remap and re-install everything at further huge cost , plus I like it as is . Contacting the tuner today to see if it can be tweeked to pass but not lose too much power that I've paid for.