CM871 runs choppy sometimes

[Bigstank]

Hey guys I need some help only cause i cant get down to Mr.hag's yet. I had him do an inframe on it @ 965k due to broken ring in #6. The motor has been running excellent but just started to run choppy while accelerating and jake breaking. Now it only does it whenever its wants and if I stop and let if low idle for let's say 10mins while I run inside she goes back to normal. When the motor has this fit it feels like I lose power but when running right she screams and pulls with full power. Now I'm just trying to see if anyone has a possibility of what's up with it. I'm thinking its a fuel related problem. When Mr.hag tore it apart all six injectors were replaced. Thanks