I have an issue with my 2007 Focus 2.0 Duratec HE.
It drives and starts fine but when it has reached working temp while driving, foot on the gas, it starts to stutter and hesitate like I'm running out of fuel, I can carry on driving but it's like it's running on 3 cylinders, loss of power and if I lift off the gas the revs will drop below 500 rpm, hunt like crazy until it eventually stalls, if I crank it over it won't start until I floor the accelerator then it will restart and drive normally for a few minutes then repeat. In a 30 min drive it will do this around 3 or 4 times!
So far I have changed the spark plugs, the gaps on the old ones were nearer 2mm! made no difference. I've cleaned and checked Throttle Body and air intake, the TB was covered in carbon deposits around the edge and engine side, made no difference, I've swapped out coils for an unknown working one, still no difference.
I'm guessing it's fuel / mixture related!? or erratic electrical fault?
I don't think it is IACV related (do I have one!?) I've had issues with a faulty / sticking IACV on other cars and it was fairly clear it was that ie the car stalled when you came off the gas at traffic lights, roundabouts etc erratic idling / hunting and the other one was a 'racing' idle ie it was too high and the car would not slow down when you lifted off the gas. So it was always in an engine idle situation. My issue is happening when I'm driving with foot on the gas.
I really need some technical help on this and you guys know your stuff!
Thanks in advance,
Phil