Here is my problem,I have a 2000 4.6 55,000 miles on it it recently developed a miss at medium to hard throttle. I never got a check engine light ,took it in to have the code pulled and it has no code i suspect it is one of the coils on the plug (it has platnium plugs) how can I figure out what is causing the miss the mechanic said to drive it till the check engine light comes on but it has been at least 700 miles since it first started missing. It is too expensive to just start changing parts. so someone give me some insight. is there a way to check each C.O.P.? oh yeah the engine idles as smooth as can be

 

Sounds like what my rig did not too long ago, but mine did throw a CEL right away.

Mine "seemed" to idle well too, but I had a dead Coil on Plug. Good ol' # 4. They said the heater hose was dripping on it. I know I have checked it before, but..........

Since you don't have a CEL, the dealership is not going to be able to do anything for you....... If you've been going like this for 700 miles, then it must be something else.

The CoP's cost about $50 each from the dealer. At least that's what they charged me....... I'm not sure how you go about checking them, but I'm sure there is a way with a Multimeter. You just need to know what the measurement is and where to attach the contacts....... I "think" that info is in a shop manual for these rigs.....

Good Luck.....

 

well as I suspected it was one of the C.O.P.'s the #3 to be exact.
at about 1000 miles after it first started missing it finally tripped the service engine soon light and thru a code. at least it's on the passengerside...now the fun begins...

 

From your symptom (medium-to-hard-throttle miss) I would focus first on a dirty fuel filter.