I've never seen a JTD injector (Bosch part number 0445110119) with a number and letter in the circle, just a number 1, 2 or 3.I take that back...there is a slight difference. Original I grade 2, new one is 2C...is that going to make a difference do you think?
If your EGR is working fine with no errors, then it must be moving open-closed okay.. otherwise you would likely get an error...
When my EGR was sticking/before I cleaned it and blanked it, I only noticed that the car was slightly lethargic. More accurately, I noticed it was more nippy and ran more like it should after I cleaned the valve/blanked it off.. It wasn't ever lumpy, but it's performance just wasn't as sharp.
If/when you remove the plastic trunk from the intercooler/to the Throttle Body, it's worth having a peep into the inlet manifold. My previous owner had run the car with the oil level at/or slightly above MAX and the car had vented a lot of oil into the inlet manifold. My MAP sensor (on the back of the inlet manifold) was similarly full of oil/coal sludge.. so I replaced it at the same time as I was tinkering with the EGR, just so I knew they were both new/clean and ought to work properly.
Your MAP sensor might be similarly choked, so it's worth a look, since without a lambda sensor, or anything too sophisticated in there, a weedy/clogged MAP sensor might affect the fuelling at idle. If you remove it and just spray it with WD40 or Contact cleaner, see whether that changes the lumpy idle. If it helps, but not completely, then a new MAP might be a good investment. If cleaning the old one makes no difference at all, then a new one could still be a good investment but it's more of a punt.
I would also stick some kerosene in the tank to help keep the internals clean, including the injectors. About 250ml of Wickes/B&Q "Turpentine Substitute" will do the job, per full tank of diesel. Not White Spirit or Brush Cleaner etc.. but the beast will burn those too.. just more smokey. If you have gum, varnish or clogging.. it'll help shift it. I've also used Cataclean for diesels.. which seems to be mostly Propanol, and 2-Ethylhexyl nitrate (2-EHN) which is a cetane improver (50ml per tank of that one) .. and it all helps ignition and the removal of black goo. I'm always "impressed" how black the oil turns and how quickly. Diesels are nasty, really.. 
The airbox and the catch tank also need to be clean. You have to remove the "octopus" pipe from the MAF sensor to the crankcase breather.. and the metal intercooler pipe... replace the air filter (you can't open the lid much more than the bare minimum to take the air filter) and clean out all the oil that you'll find in there. Mine had pools of it (from having been overfilled most likely, as it's never been as bad since I started only filling it to 80% of MAX).
Also check ALL these pipes for leaks. There's a dozen different pipes and connections... particularly the short stubby one connecting the turbo to the metal pipe to the intercooler. Mine was an OE silicone job, but was perishing and leaking "oily vapour" all over the front of the engine.. A leak here would be bad for your idle, since it's un-metered air the ECU doesn't know about. Your lumpy idle is hopefully just an air leak.
Ralf S.
If your EGR is working fine with no errors, then it must be moving open-closed okay.. otherwise you would likely get an error...
When my EGR was sticking/before I cleaned it and blanked it, I only noticed that the car was slightly lethargic. More accurately, I noticed it was more nippy and ran more like it should after I cleaned the valve/blanked it off.. It wasn't ever lumpy, but it's performance just wasn't as sharp.
If/when you remove the plastic trunk from the intercooler/to the Throttle Body, it's worth having a peep into the inlet manifold. My previous owner had run the car with the oil level at/or slightly above MAX and the car had vented a lot of oil into the inlet manifold. My MAP sensor (on the back of the inlet manifold) was similarly full of oil/coal sludge.. so I replaced it at the same time as I was tinkering with the EGR, just so I knew they were both new/clean and ought to work properly.
Your MAP sensor might be similarly choked, so it's worth a look, since without a lambda sensor, or anything too sophisticated in there, a weedy/clogged MAP sensor might affect the fuelling at idle. If you remove it and just spray it with WD40 or Contact cleaner, see whether that changes the lumpy idle. If it helps, but not completely, then a new MAP might be a good investment. If cleaning the old one makes no difference at all, then a new one could still be a good investment but it's more of a punt.
I would also stick some kerosene in the tank to help keep the internals clean, including the injectors. About 250ml of Wickes/B&Q "Turpentine Substitute" will do the job, per full tank of diesel. Not White Spirit or Brush Cleaner etc.. but the beast will burn those too.. just more smokey. If you have gum, varnish or clogging.. it'll help shift it. I've also used Cataclean for diesels.. which seems to be mostly Propanol, and 2-Ethylhexyl nitrate (2-EHN) which is a cetane improver (50ml per tank of that one) .. and it all helps ignition and the removal of black goo. I'm always "impressed" how black the oil turns and how quickly. Diesels are nasty, really..
The airbox and the catch tank also need to be clean. You have to remove the "octopus" pipe from the MAF sensor to the crankcase breather.. and the metal intercooler pipe... replace the air filter (you can't open the lid much more than the bare minimum to take the air filter) and clean out all the oil that you'll find in there. Mine had pools of it (from having been overfilled most likely, as it's never been as bad since I started only filling it to 80% of MAX).
Also check ALL these pipes for leaks. There's a dozen different pipes and connections... particularly the short stubby one connecting the turbo to the metal pipe to the intercooler. Mine was an OE silicone job, but was perishing and leaking "oily vapour" all over the front of the engine.. A leak here would be bad for your idle, since it's un-metered air the ECU doesn't know about. Your lumpy idle is hopefully just an air leak.
Ralf S.
This stuff!!
Thanks Ralf, a font of chemical knowledge! I will try some next time I fill up, thank you. Have an new issue with electrics, so attention else where!! Did you ever send off you dash for repairs?!