Spluttering ?fuel injectors

[gcgregory]

I have had my Q5 3L diesel for over 10 years now, and it is approaching 200,000 miles (320,000 km currently).  I just had a gearbox failure which thankfully was just a broken fluid pipe and a replacement/ fluid change fixed the problem.

I also have spluttering at idle, and when I just start moving, I am thinking this could be the fuel injectors.  I have never used the additive.  It is worth trying it, does it work?

I have been looking at a replacement Q5, but all the diesel and even the most of the petrols seems to be slower than my current car - my car has 240BHP/ 500 torque and does 0-60 in 6.4s.  Only the top of the range Q5 50 TDI manages this now!