I had a similar thing with my EF - and having a big cam and loud exhaust it was bloody humiliating to have it missing and carrying on at idle and stumbling on takeoff. Mine would actually idle fine for a minute or so immediately after startup cold.

I finally got rid of it by replacing the injectors - then a couple months later the exact same thing started happening again - WTF!!

I got ANOTHER set of injectors and realised that the inside of my fuel rail was rusty as hell - full of flakes etc. - so I fitted a new rail along with the replacement injectors and she's still happy as larry over a year later.

Another issue I had was a "flutter" under acceleration - randomly and at various loads and revs. Sounded and felt EXACTLY like a dropped valve!! I fixed that by unplugging the Cam Phase Sensor... - I s hit you not she starts and runs fine with it dosconnected and no more stutter.

SOLVED!!

After re tuning and setting the base idle correctly as mentioned by creeture3 which is now over 2 weeks ago, I was under the impression that the idle fix wouldve worked straight away.

Dissapointingly, i thought that i would never get to the bottom of the issue. Driving the car around for at least 2-3 days, i had noticed that the idle was smooth and no more cut out!! The idle is spot on now and is fixed for good, as i havent had any problems with fluctuations since.

One important step i missed out on....resetting the ECU after the base idle adjustment. I gather that the car's computer was re-learning the change and had adjusted itself after those few days.

Either way, its all good and wish to extend many thanks to zabatron and creeture3 who had instructed me to reset the base idle the CORRECT way.

Now faced with one last problem of a hard cranking issue...continuous cranking whilst warm....it eventually starts but takes ages to crank.

Its had;
New fuel filter
New pressure regulator
New injectors
New fuel pump relay
New Coilpack
New Leads and sprak plugs.

.....might be dodgey ignition barrel PCB (at the end of the ignition barrel), but BCM is ok as interior light works fine.

The transmission inhibitor switch is playing up as i need to shift to N most of the time to start.....if i replace it, reckon that it might start up without cranking too long??...

*sigh*

Cheers for the help guys!

How dirty is ur crank sensor? - I know I haven't had any hits yet with ur issues - that idle setting business is an eye opener (I HAVE long advocated that people SHOULD set it all properly - but really didn't think it could cause your issue - one for the books! ) - BUT - a few years ago a good clean away of gunk buildup round my crank sensor righted a lotsa crankin before starting issue that developed pretty suddenly. Went back to firing up within couple of cranks.

Hey, yeah the crank sensor was replaced about a year ago for a new one. I haven't checked for any oil leaks around it but can't assume its dirty as its not leaking oil anywhere at the front of the engine.
Any way to test the crank sensor without removing it?

I also didn't think that the base idle tune could throw things outta whack so much either..im ecstatic that it had fixed the issue I've had for almost 2 years!!

Cheers mate!

Hmm newish sensor tends to rule that out - but it might still be worth at least unplugging / replugging it's connectors - there's the one on top of the sensor itself - and another over near the cam sensor (in other words there's a short loom with connectors each end for that crank sensor - Ford ). And maybe still worth givin it a squirt with degreaser or contact cleaner in case there's grunge with magnetically conductive component on the face

I think there are ways of checking the sensor with a meter but I don't have that info sorry.

Ok, will check it out and give the contacts a good clean with contact cleaner. Will post back later on findings.
Cheers