I have a 2009 Fiesta zetec s with 80k on the clock, when i got the car i noticed when started after its been sat for a few hours it jerks under acceleration for a few seconds however it runs perfectly immediately afterwards. The only other thing i have noticed if a slight burning smell after a long drive, which i presume is old oil on the engine because someone didn't push the dipstick all the way in.

I thought it could be spark plugs or ignition leads so I've replaced both of these however i still have the problem.

Has anyone else experienced this problem of know what it could be?

Hi id change the plugs and leads first if not you're probably looking at a coil pack. I would recommend taking it to someone with an obd reader who should be able to tell you exactly what it is causing the fault.

Certainly sounds like its misfiring on one of the cylinders

Cheers for the reply, I've already changed the plugs and leads, also there is no other noticeable effects, no loss of power mpg is around 37 and idles fine

Mines a 56 plate and was doing the same especially in the cold weather. Had it serviced last month( oil, oil filter, air filter) ford value service £115 which includes 12 month breakdown cover. It's been running perfect since :)

Hmm I might give it a full service at the weekend then since I've got the parts sat here

Certainly worth trying a service :) wont do it any harm atleast. Like I said my mk6 was the same itd run quite rough when it was cold then once it had heated up it was absolutely fine and it was a faulty coil pack