Glad to hear that you are up and running.
... they were supposedly set up correctly an all but he said you are supposedly supost to tune them .. and his fine 35K machine will recognize them but can not talk to them... thanks to all
I haven't heard it referred to as "tuned", but I suppose that fits. A more common term is "coded".
My take on injector coding.
The injectors are not able to be manufactured to strict standards. The size of the "squirt" can vary. The injectors are tested and assigned a number code which relates to the "squirt" quantity.
When a new injector is installed then the specific injector code number can be submitted to the ECM (engine computer) so the injection quantity is a known value to the computer.
The ECM constantly monitors the engine operation which includes varying the injector "squirts" based upon feedback.
I replaced all 5 injectors in my 2004 with Bosch factory reconditioned injectors. As happened to your mechanic, I was unable to get the ECM to accept the new injector codes with my DAD. I never did code my injectors. My engine has been running fine for many tens of thousand miles.
My opinion.
The injector coding helps the ECM to trim in the fuel quantity more quickly after new injectors are installed. Because the ECM is constantly monitoring and adjusting the injected quantities based upon feedback, my theory is that eventually the ECM gets the injected quantity trimmed in whether the new injectors were coded or not. I stopped worrying about it quite quickly for my engine although I would have preferred to code my injectors.
All that said, I readily defer to any professional Sprinter technicians who disagree.
The following documentation should help to support my ideas above. vic
Particularly note the first sentence below:
The ECM compensates for both injector variations due to production tolerances as well as due to injector wear
over the life of the injector.
20140522 edit: Given the 3200 RPM comment above, it may be more critical for injector coding if you often operate above that engine speed. I typically do not. On the other hand, above 3200 RPM a bit of difference in injector balance may just not be that critical as all the fuel injected will be burned efficiently.