ok.. I missed few precisions to shorten the story, but let me add few prcisions:
1- With the stock Intake + KKM kit (old setup) I had the bucking problem at low rpm, but never saw the CEL. I usually just down shifted a ratio to avoid staying in the 'sketchy' rpm zone.
2- The EGR ports were not clogged on my old UIM.
3- After replacing the whole intake, the problem stayed the same. No improvement. Since the MAF was replaced, I think we can remove it from the equation (unless the problem is in the connector.. I'll look at it). And only once I had the CEL trigerred and I saw it happening at the same moment I was holding the engine in the problematic condition (very light throttle, engine rpm below 2000 rpm, bucking..). I just reset the CEL, we'll see if it comes back.
4- I just come back from taking the EGR valve off the car and it seems fine. It is actuating when I put vacuum on the top.
IAC? That could make sens since my problem happens at very light throttle position.. Maybe it would also explain why the car dies when I gently pump the gaz pedal at a stop.
Could the DPFE cause the "bucking" at low rpm?
People told me to look at my fuel pump, but I would more believe the fuel pump (returnless system) to cause problem at high load/rpm.
