'98 Expedition seems to lose power...

I have a 1998 Expedition XLT 4X4 with the 4.6L V-8. Lately, while driving down the road, it doesn't seem to want to keep accelerating. The more I press the pedal, the more it seems to bog down until I release the pedal and then it's usually fine...for a while. It's not extremely noticable, I can just feel that it won't respond. I need to change the plugs, which I've been putting off, and was curious if this could be the problem. The check engine light came on awhile ago and the code was for a #1 cylinder misfire. Also, should I replace the coils when I do the plugs and wires (it does not have a distributor)? Any help would be greatly appreciated...my wife is scared to drive it until the problem is fixed.

the spark plugs are designed to run 100k, if you'vr got a misfire, and the engine feels like it's shuddering, then you've probably lost a coil, and to have the dealer replace them, run's right at 250$$ a pop, and i just had my spark plugs changed in december, again another 250$$, and prior to the tuneup, i lodt 2 coils in november.
hth
Rick, Ore

Thanks, Rick, I figured I'd go ahead and change the plugs, wires and both coils since the mileage is 117,000. I'm gonna go ahead and try it myself...those prices are a little steep. Thanks.

Anyone have any other ideas on this before I get started on maintenance?

Also, can anyone advise on whether or not I need to put anti-seize on the plug threads before installing them? And what is the proper torque for the plugs? Any help would be greatly appreciated.

With the description you gave of losing power when pressing further on the pedal and smoothing out when you let off sounds like the fuel filter plugged or the fuel pump going bad. I would first get a fuel pressure tester to check the pressure. If it's low replace the fuel filter first after relieving the pressure. Then run a fuel pressure test again, if it's at the correct pressure after that and road tests fine then your good to go. If not then replace the fuel pump and pickup screen. Not a fun job since it's inside the fuel tank. I've done 4 various vehicles and that was the fix on all of them.

Oh and yes on the anti-sieze lube for the spark plugs especially in aluminum heads. Here's an extra tip, use a short piece of fuel/rubber hose on the end of the plug to install with your fingers to avoid cross threading them into the holes.

Thanks, I'll let you know how it goes.