I've been having issues with my ford focus cmax 2.0 tdci. It's randomly loosing power while driving and won't rev/move (also rough idle in the morning). I had the crankshaft censor changed, it was fine for two weeks then same problem again, I then sent it back to the garage and they apparently replaced the EGR Valve with a used one in a good working condition, however on the way home it happened again! Just lost power and seemed to go into a limp mode.

I've had the car diagnosed at a different garage, and the codes that came up suggest that it has a problem with the EGR Valve.

My question is: Is it possible to get the EGR changed on these models and get the engine running without programming/re-calibrating? I'm worried the mechanic either didn't change the EGR valve at all (they just cleaned it), or they changed it but didn't re-calibrate it?

TIA