right people my ST escos has a little missfire here and then mainly in 4th and 5th very rarely in third

i have changed the plugs but still the same, i was thinking about maybe changing the coil packs

but i havent a clue where to buy coilpacks from

anyone have any ideas

thanks in advance

 

http://cgi.ebay.co.uk/GGR550-Ford-Es...QQcmdZViewItem

 

Get it on a rolling road, the operator can run tests to find out what is breaking down or faulty under load rather than just replacing bits & hoping it fixes the issue.

 

you say new plugs but what gap you running and the coilpacks are the same as one of the scorpios.

and what boost?

 

Get it to a tuner for proper fault diagnosis mate. it may only be a plug gap thing or it could be coilpack replacement which is circa £200, leads £30 approx and good plugs £30 approx. A set up is a lot less than this lot put together

 

As Red says Where abouts in the country are you mate? And what sort of misfire is it? Big violent bang bang misfire or a soft "fluffy" one that you can drive through? Where in the Rev range is it happening, full throttle, part throttle etc? Any other symptoms, is the rev counter jumping around etc?

Good place to start is check all the electrcal loom plugs are clean and tidy, the two big fat ones on the passenger side inner wing are a favourite for water ingress and corrosion, and cause misfires.

I would use MSD, can't get better IMHO, thier number is in my sig and they are very very helpful