I had a mechanic sort my turbo out a few weeks back, and he mentioned that it sounded like one of the injectors was going bad. I've suspected this myself for a while as things are pretty rattly. I haven't done a leak-off test or anything to confirm this, but I'm wondering if I can get in a pre-emptive strike and arm myself with a bit of information about injectors, before the proverbial hits the fan.

If an injector fails (Injector <n> above knock threshold), what happens? Limp mode? Total breakdown?

I have an F-Super - is it possible to recode the existing injectors? Is there any point?

If I need to replace, should I replace all four at once? Or just the bad one? I'm concerned about cost as I know the Delphi injectors are not cheap.

Finally, is it a job I can do by myself? I know my way around a bag full of spanners.

it's not a difficult job, you can do it by yourself all you need is the right tools. Also, you don't need to replace 4 of them just replace the one that is bad. You can try and clean it first and see how is going, but if not you will need to replace it.

What i have read but am not sure about that is that you will need to program the one you are going to replace for TDCI engines only, but am not sure. I replaced fuel injectors many times but i haven't program any of them, just simple replace and it works like a charm.

OK. Soooo.... what happens if an injector packs up? Breakdown callout?

I think maybe I should do a leak-off. £35+ for a proper kit tho?? Jeez....