2006 1500 with 4.8 vortec engine.It cranks normal and runs normal most of the time.After it warms up sometimes you can be running at cruising speed and you can feel a slight bump or hesitation.I can accelerate quickly and it runs normal but when just "feathering" on the accelerator it will bump or hesitate again.It seems to do this after it warms up and its just random not all the time.Also sometimes when I floor it the check engine light will come on and blink but will go back off.I changed fuel pump,installed # 8 cyl coil pack and removed and cleaned injectors.New plugs and wires were installed a short time back.Any suggestions appreciated