P38 Diesel Hickup then no power

Hi all, got a 96 2.5 diesel P38,
since i've had it its had the intermittant overrun injector light come on, but had kept driving it since and have just adapted my driving style to avoid it happening much.
it seems low on power in general (although i havent driven a different one to compare) and am planning to get pump timing checked soon.
i have read differing opinions on the injector light coming on, some recon it will be no4 injector and some say pump, was planning to re-nozzle all 6 injectors soon but on my way home today it hiccupped violently a couple of times and cut out when i let it drop to idle, it re-started and carryed on driving and hiccupped a few more times but seemed down on power, then the injector warning light came on constantly. i tryed driving up my lane (Very steep and off-road) but it didnt have the power to make it up so had to park at the bottom. had a quick glance under the bonnet but nothing obvious. under no load it revs cleanly and freely, and is boosting ok (boost gauge recently fitted) but under load it struggles to even pull away on a hill. i'm thinking number 4 injector has stopped pulsing at all and it has gone into limp mode? but i have no way of reading codes at the moment, and am away from monday morning 'till next sunday eve so can't do any diagnostics on it this week, so was looking for peoples opinions. also is there anyway of manually reading fault codes e.g bridging connections to get flash codes?

cheers
Adam

I think you`ve answered your own question: yes it`s probably #4 injector, or the FIP. Getting the fault codes read, (as I understand it) will point to a fault, but won`t definatively say which of the 2 it is. The injector #4 is a lot cheaper and easier to replace!
(Assume the intank fuel pump is good and filters clean.) I`m not aware of any short(cheap)cuts on reading fault codes.

Number 4 injector is most likely but as gt said check the in tank pump and the filter.
I can tell you how to read the engine codes without a reader using flash codes, it's quite hard and takes several attempts but it does work. Let me know if you want details. The fault list is too long to type up on here so I would need an email address to send it as an attachment. PM me if you want it.

just read codes on mates AA laptop and sure enough its needle lift sensor.
cheers all