Hi I've got a focus mk2 duratec 1.8 he petrol . Faults are when driving on motorway for 30ish minutes on acceleration slight twitches are fel especially towards 70mph. The main problem is if I come off mway on to urban roads and accelerate quite quickly with each gear at about 2500 rpm it jerks about 3 times like if you put your foot on accelerator and take it off quickly.Also after this accelerating from traffic lights it is sluggish and jerky. If I turn off and then on performance improves for about 30 mins. Plugs and four coils have been changed cheers. Ps I.ve been told it could be swirl flaps.