Q: Hi I have a 07 impala 5.3 and I've been having an issue when I try to accelerate if I give it to much gas it starts to buck and he

Hi there. It sounds like you may have a low fuel pressure concern. A car can idle with low pressure, however when demand is placed on the system it will fail as in your case. The engine is possibly starving for fuel to adequately keep up with demand; increase in throttle, load, and speed demands more fuel. There could also be other underlying issues creating or adding to your concern; electrical concerns, air metering concerns, contaminated fuel, etc.. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a hesitation and bucking concern [https://www.yourmechanic.com/services/car-is-hesitating-and-bucking-inspection].