Ideas to fix my 1.5dci scenic?

It is possible the injectors are slightly blocked. An easy way to possibly remedy this is to build a high vacuum in the engine to pull anything through them. To do this travel down a steep hill at speed (100 km/h; 60 mph) in a low gear (drop it into 3rd or 2nd if its a 5 speed; in a 4 speed auto drop it into 2nd). You want the revs good and high, close to red line. Give it some gas to open the injectors. It may not work first time. I've done this with success before, but I had the advantage of hills on my commute, so did it until it was better. You can also help by adding injector cleaner to your fuel. Doing both is only going to improve your chances.

Jim Fixx
February 2010