injector problems 2008 citroen dispatch

[Ian M france]

Hi my dispatch was due its pollution test it is a 2008 2.0 hdi (later shape) with common rail fuel injector, I put some injector cleaner in a tank of fuel and was driving it a little bit harder than I normally do to clean everything out. One of the injectors stopped working, I have had problems with it before but it was always a connection problem and a clean up of the contacts normally gets it working , but this time it did not come up as a fault and engine light did not come on, but if you remove the lead to the injector it still runs the same (light did come on when taken off connector)
I had a spare injector (well 4) all where working but that was 3 years ago. This one jammed and let diesel through, so bought new head for injector and tried to make up a good unit I have tried about 5 different combination, none work I have swapped cylinders and problem moves with the injector.
All the solenoid heads have same resistance as the other injectors about 180k and they do not turn engine light on so think they are okay have clean all parts and would think if dirt was a problem it would work for a bit then stop but that cylinder just will not work, I cleaned the heads of the other injectors (they all work great) as decided to sort out some other problem so took manifold/ rocker cover off, changed return pipes and injector seals and also egr, valve
might have to get a recon unit but would hope to get it working with all the bits I have anyone any ideas how I can test bits?

[Ian M france]

Hi well recon injector arrived today fitted it and still looked like it only running on 3 cylinders, took electrical connector off new injector and nothing changed, so swapped 2 and 3 over new injector from 3 to 2 , took electrical connector off 2 (new injector) and engine ran the same, then tried taking connector off the injector in cylinder 3 engine run the same engine running too well to be running on just 2 cylinders, took van for a drive van drives okay and I am quiet sure it is running on all four cylinders, had a look at fuel pressure it was 250 bar at tick over could this be the problem, goes up to 450 bar when revved think it should be 300 at tick over?

[Ian M france]

Cleaned fuel pressure regulator now getting about 290 bar, used it today still ticks over the same but was able to use it