Ra Rodeo Hfv6

I have a Problem with a 2007-08 HOLDEN RA RODEO , with the new HOLDEN HF v6 ENGINE!,(170 with out variable cam shaft timing). It has a slight surge at 2000-2200 rpm in 3rd gear (manual),note on smooth road you can feel it in second, 3rd and 4th at this rpm ,at times, It has done it since new, it has only done 4,000 km. The dealer has checked out, fuel, fuel filter, fuel pressure while driving,checked plugs ,coils, o2 sensors , fuel vapour purge system. They tried new injectors , no change.They have reviewed ecm data,but nothing shows up??:banghead: :runaround:
Has any body heard of this with this engine and or got any ideas ???:)

can you make it happen at other rpm? just a guess but it could be a drive train issue, not a motor issue.