Engine miss

[ronbo57]

1998 Ford F150 all stock 4.6 . Engine miss. Original code said misfire in 2 and 4. Replaced all plugs with new Champion platinum. Still have problem, but much better. Seems to smooth out when warmed up good, but definite miss when loaded up (Stomp on gas or speed up quickly) Replaced driver side coil pack, still has problem, no check engine light. Parts guy said run all fuel out (as it is over a year since last ran) Have not replaced plug wires yet. I will run it tonight and look for the obvious. Next step I plan is run the fuel out and replace the fuel filter put in some higher octane, unless someone has experienced this problem and has an answer. Thanks in advance. Ron

[Bluegrass 7]

With the truck setting that long, the gas could be stale.
Do all the normal maintance for fuel filter, new gas, water absorber, even fuel injector cleaner but not all at the same time.
Then see what you have before going back to ignition checking the plug wires etc..
BTW some will tell you not to use the plugs you put in.
No problem, if you did the job correctly and used grease inside the boot tips making sure the boots and internal springs set down on the plugs and inspected the boots, they should be fine.
Good luck.