Ah, the engine that just cannot seem to run right!! 

As the title says, the issue I'm having is missing/stumbling when you command more than light acceleration below 2,000RPM.  I've replaced the plugs, leads and coil pack, to no avail.  Then it went in for a timing belt and they noticed the de-phaser/variator was worn out (rattling on cold start-up and generally noisy), so at much expense had that part ordered from Ford and replaced.  Great, I thought, now it MUST be fixed!  Got it back and no, still exactly the same (only now quiet on cold start-up).

The only thing I can think that's left to be an issue is the fuel pump, or the "lifetime" fuel filter that the garage advised the car has (when I asked them to change it).  It has 175k on the clock, and I personally would have changed the fuel filter about 4 times by now, so if it is one of those ridiculous "lifetime" filters then I'm not surprised it is restricting flow.  That said, my logic would suggest a fueling issue would be most prevalent at higher RPMs, but in this case anything from 2k-redline is absolutely fine, it's below 2k that it chugs along.

Hoping someone else has had this issue and may be able to shed some light...

have you used forscan to see if any fault codes are showing, it sounds like a problem with the ti-vct, 

Petrol fuel filters don't really clog.  It's just a mesh bag to stop lumps of sand or leaf going though lol.  Totally different to a diesel filter.

175k on a 1.6 Ti-VCT is a lot though.  I'd suspect wear rather than 'dirt' at that mileage.  Even the injectors might be worn by now.

With that much mileage, I'd be investigating the throttle body performance first

Or throttle pedal, if it's fly by wire (can't remember)

You're not the only one with this issue. I also have this issue!

changed everything you mentioned too.

 

281k km on the clock.

bugs me down!