Hi,
having a nightmare of a time with my 2007 fiesta zetec s (1.6 zetec engine 92k on the clock)
first of all one morning it all of a sudden started Misfiring on the way to work. So thought common problem coil pack, did come up with a misfire code, so bought new coil pack (gen Ford) new leads (gen Ford) and new spark plugs for good measure, made no improvement. Changed fuel filter still no better.
no lights no codes, revved the nuts off of it on the drive and it solved it. I did fill up with fuel the night before this happened so thought dodgy fuel so dumped that and in the past week Ive used over a tank of fuel on petrol I get from my usual garage I go to, so don't think it's fuel related now.
now a week later it's started to cough and loose power then idle horrendously, turn it off turn it back on seems fine till a few miles down the road does the same thing.
no coolant loss none leaking onto plugs from coreplug, still no lights or codes coming up.

really have lost my patience with it now, any ideas???

 

Do these engines have cam or crank sensors on them?
Also unplug the mad see if it runs any better

 

Changed the cam sensor as thought could be fuel related.
Havnt tried running it with the map disconnected

hate modern cars!! Much prefer my Xr2 lol

 

could be a software update for this. my sons car had this as it stopped idling one day there were no faults but the update cured it.

 

Will be calling fords tomorrow to see what they say, Ive had the car a long time and have kept it going nicely, it's really pi$$ed me off I can't fix it this time.

 

Found the problem last week, thought I'd look at the loom in the dark and just like that a little wiggle and a spark appeared!!
wiring from the ecu plug down towards the battery tray had been chaffed causing it to spark in certain positions, the wire was the one that went to the coil