I didnt read all 20 pages... But I was triggered by the first post
I had the same problems with stuttering, wish I found this thread earlier. I Got my complete DPF removed, because of these stuttering (and other misbehaviour
).
I tought some gas valve was a little crappy, or that it could be the EGR. I had my DPF removed and a JD-Engeneering chip in it. It is one of the highy rated dutch tuners. I was told the EGR should not work anymore, because of the chip.
I got the injectors cleared, nothing helped. Then I asked to clear the intake and EGR. THEN they found out, the forgot to place this EGR-shut-off-plate
. So they placed a same sort of plate on the same spot, and now I didnt feel these stutterings anymore.
For every TDI since 2006(I believe) there need to be made some software adjustments. Maybe's it's nice to put this in the first post. If (on >=2006 models) the EGR is shut off with a plate you will get engine faults. Probably the 'Engine Light' will light up.
So for every one having stutterings... Do the plate AND an software modification.
(ultrasone cleaning of the injectors also helps to give a better ride)
This is how my EGR valve looked after 130.000km:
This is one injector (left) before and (right) after cleaning:
Notice the clean nozzle!