New 4l60e trouble

[Mike reeves]

I just had trans in my vy clubsport recond to factory specs with a stg2 shift kit.1-2 shift great 2-3 3-4 flare slightly (500rpm)when the rpm is above 3k maybe half throttle.the others thing is it sometimes goes flat and powerless after a gear change. The mechanic recons it could be the computer retarding the engine for some safety reason? Does this sound normal or has anyone else seen this? Thanks

 

[Immortality]

Take it back to the trans shop as first port of call. Flaring suggests something ain't right.

 

[Mike reeves]

That's where it is at the moment. Just frustrated has it went in with one problem and came back with 3.