Hi guys, hoping one of you can shed some light on what might be problem with my 2001 2.2 DTi. Mileage 113,000, only owned for 3 months, had a recent service oil, filters etc, used FORTE Diesel Fuel Conditioner in fuel tank, noticed that when putting foot flat to floor, delay in turbo coming in (not normal turbo lag I don't think) Also a touch of jerkiness from engine every now and then at lower speeds, and has cut out a few times when moving off from a junction? Bought a cheapo new air flow meter of  bay of e, cured top range turbo lag (car seemed to fly) but bottom range car jerked even more and was almost un-driveable at thirty -40 miles an hour! Also caused car to go in limp mode! Had to put original air flow meter back on car. Really confused. By the way had voltage check done on air flow meter and voltage was 4.3 or whatever it should have been? Could air flow meter still be problem? Don't want to spend 100 plus if it's not meter. Thanks guys. Take it easy