Scenice 1.9Dci - Renault Scenic warning message - brasero

hi there ,

I keep getting a message saying that i should have a "control "on the injection ( its a french car so hence the translation ) , I have taken it ti a couple of renault garages here in Frane and 1 fitted a new fuel filter which seemed ok for a couple of days then the message came back ; the other garage says that they cannot find a fault at all .

basically it seems to come on everytime i am driving uphill , the car seems to have no power and is sluggish then the message lights up .

after the garage has had it for a day and a test drive it seems to come back fine for a couple of days and then get the same problem again.