nufan

It's been about 2 weeks since I got my SP (and boots) replaced (and tranny flush/filter) and my 04 FX4 is still idling rough and seems to have no "guts"

It trough codes twice for cyl 3 misfire, but never showed any abnormalities when brought back to the shop.
They took it, re-torqued the plugs...ran great from a day, then got rough again.

It's not terrible, but worse than it was. No codes, but rougher and no guts either.

thoughts?

Where is a less expensive place to get coils? I'm thinking that is my next move.
But why did all this happen right after new motorcraft plugs???!!!

FYI: 93k on truck, 5-30 Mobil One used, fuel filter changed, SP and boots.

j.low

Have a '97, 4.6, 234,000 miles since new (California). At about 150,000 miles it started the rough idle off and on. A periodic rattle developed somewhere in the engine. No mechanic could figure it out, it never had a code. On a trip last year (228,000) the power started to tank and on a big hill the check engine light came on. A shop put their analyzer on it and it showed "complete catalytic converter failure."
$2,400 dollars later (four cats and four O2 sensors I had a new truck.
At that point some things became clear; one, bad cats apparently host many problems and two, stop putting additives in the gas to cure unknown problems.
This may not be your trouble, but it's worth a check.
Good Luck.