North Star tb and maf . Idle issues.

[gbgn1]

I've got a n* throttle body and maf on my car. I maf tuned it and it runs great. Problem is if I rev the car say 3000 rpms . When the rpms come down usually its unstable . And sometimes it just kills the motor. Is this a known problem? Should o go with a 5.3 cable throttle body? And maf?
Thanks!!

[SgtMarshal]

I would double check the security of the throttle cable in the throttle body and make sure it is pulled all the way to the end of the channel. your idle sounds like it's either a throttle position sensor issue, or the maf is defective.

[gbgn1]

I've tried multiple tps , with always the same result. The tb isn't hanging up in anyway. Haven't tried a different maf but the car runs great . Just the issue under hard throttle.

[SgtMarshal]

can you swap the original throttle body back on and see if the problem goes away? I would do that before I went and bought a new maf.

it could be a vacuum leak, how do your fuel trims look?