car bucking at port throttle and dies at WOT

[wiked87gn]

what could be causing this, it bucks at part throttle then it dies at WOT millivolts drop to almost 0 at wot as if it wasn't getting enough gas, just recently had ECM modified for 72's, with extender xtreme,new LSI maf and translator plus put in and the car was running like a champ until this started happening, any ideas are welcome..

 

[PsychoBuickBoy]

Do you have an aftermarket cam or the stocker?

I just ask cause I had similar problem and i was praying it was a coil pack or MAF but found out it was a flat cam lobe

 

[wiked87gn]

aftermarket cam,ported heads ported intake,extender extreme, 72's, 3.5 ls1 maf,trans+, T66 ballbearing turbo..