Hi lansyp, I used to have a 2002 x-type 2.0D. My car occasionally misbehaved in a similar way. I saw an episode of Wheeler Dealers (at least I think it was) and the mechanic Ed China couldn't sell it any better so I gave it a go. It made a big difference to fuel economy, reduced smoking, improved the torque and improved starting. I think it cost around £75-£80'ish at the time and I believe I got my money back on fuel savings that year. Sadly the car was written off parked up overnight in Shrewsbury when a drunk driver ran into it.
Edited by GeeMeister (21st Mar 2015 9:21am)