Hi,

My ford focus has a misfire, almost like it is running on 2 cylinders. I chaned the coilpack yesterday and it started running fine but the misfire has come back again now.

Has anybody got any idea what it could be? It's a bit strange how changing the coilpack fixed the issue for a day and then it came back?

Cheers,
Dan

 

Same pistons misfiring?

They can fail from new but not often.

What size engine is it? Does it have a MAF sensor?

 

you need to change leads ,coil pack and plugs at the same time mate,as they can sometimes damage the new coil pack.

 

If the coil pack came from Ebay and is not a Ford item, change it.

 

I would also be changing leads and plugs next.

 

+1 on leads

 

As above leads, plugs and coil pack. Knackered plugs with too large a gap will knacker the coil pack in no time.