Engine still "pops"

[Walter Joy]

It's been a while since I've been on here so I'll see if I can get some help. I leave for Carlisle next week and I'm not too too concerned about the truck making the 160 mile trip but one thing that has been bothering me is the truck still "pops". What I mean is it seems to be a little boggy and sluggish and then when you try to accelerate it seems like the butterfly valves snap shut, and a pop is heard. Lasts a split second and then returns right back to normal. Distributor cap, rotor, and spark plug wires were all replaced in Spring 2015. More recently, the throttle body had all new gaskets put on, new plugs just put in, brand new Hall effect, new injector seals in the throttle body, most of the sensors and other doodads hanging off the throttle body (everything except the IAC), brand new radiator and hoses, and a brand new engine coolant temp sensor. The only thing that has caused problems is the engine coolant temp sensor may be wrong, as initially it caused the throttle to stick but after being unplugged it seemed to fix it. So is it a faulty fuel pump or what? Fuel filter also has been replaced too. And when the coil was replaced, the dielectric grease actually ran out like water. It ran fine for a few days but after that it popped on me. We can not replicate it standing still and only happens occasionally, sometimes in the rain or on a hill or going around a corner but also sometimes accelerating on a straight flat ground

 

[ROtruck]

Check out my woes! Years ago when my truck ever first did anything wierd like a "pop" I found that a plug wire was touching the exhaust manifold to the point of being melted. Used an old wire from previous set. Problem solved. But now...