I need help!! I read tons on this without finding any 100% fix! My 04 f150 4.6 v8 has started hesitating upon acceleration and falls flat when I press the pedal, then after a bit it kicks in and takes off. I've replaced TPS, fuel/air filter, did sea foam and nothing. Plugs and cops were just changed not long ago. I'm not getting any codes or lights. Is it still possibly a bad cop or fuel injector?? Need help! Thanks!!

 

I just dealt with what you describe (hesitation, surging in all gears) on my '06 STX with the 4.6. I replaced the fuel pump driver module first but pulled plugs and coils when that didn't solve the problem. What I ultimately discovered was substantial oil in the plug wells of #6 and #7 which means I have a valve cover gasket replacement in my future. I should note that I never got a check engine light. Hope this helps.

Update: I just realized how old this post is. Hopefully you already solved your problem.