Flatlander wrote:

Injector fuel trim points to 'a' problem, not 'the' problem. an injector spill or leak-off check (same thing, different terminology) along with checking actual values in the fuel system would be a good point to start

Hi

Wished to say many thks for the figures u quoted in the other thread as good to know what they should be

“ acceptable range is 700-1300, 600 & 1400 are the min & max trims before a relevant DT”

  

Breg90 wrote:

See this thread:

https://www.disco3.co.uk/forum/need-replac...02536.html

also a big thks as was also interested

  

gstuart wrote:

Hi

Hope u didn’t mind but just turned the pictures for u , sorry can’t help ref the injectors

Plus welcome to the asylum

Ps, plus not wishing to sound rude but when u get chance plse fill in ur profile as then it will help others know what model / year of discovery u have , thks





Thankyou for spinning the pics round

Breg90 wrote:

Have you been for a nice long run before checking the injector balance?
What other issues do you have that might be causing over lap? HPFP pressure and pressure control stability?

Mind that the engine can't measure fuel flow through the injectors, but it can measure crank speed and knows that if speed increases excessively after a particular cylinder fires then that the injector is likely flowing more fuel than expected. So over time it will cut that injector back to compensate & vise versa if the spedd has dropped after a particular injector fires. Note injector numbering follows the firing order, i.e. it fires at injector 1, then 2, 3 and so on.

You have lots of injectors at min flow, one at max. I'd wager the one(Injector 4) at max flow is compensating for an earlier increase in crank speed - I don't think this is your issue.

I'd guess that injector 5 is cutting back as injector 4 is at max and is 'over compensating' for what is happening earlier, hence driving an excessive increase in crank speed, so injector 5 has to cut back (rippe, effect).

Beyond that I am not sure. Have you considered taking out the injectors for flow testing?

Or buy one new injector, fit in place of say injector 6 or 1, then let the engine run for a few days (with some long runs at steady speed, say motorway) then recheck?

I'd be interested in what you do and what the outcome is.

Flatlander wrote:

I'd also ask, what is the problem? what symptoms are you experiencing? fuel trim limits in isolation don't really give much of a clue, I also note there are EGR DTC's set - are they blanked off?