My 1999 4.6 is at 93,000 miles, and to the best of my knowledge, it is still on the original plugs, wires, and coil packs. I figured a good way to get some more power and better fuel economy would be to put in some new wires, plugs, etc. Any suggestions on what type I should use? I'm not looking to go full race mod on the truck, just pick up some more power. Also, where can I find these parts?

 

Why not replace them with OEM parts from a parts place?

 

i agree with Pony Rider, i've owned two 4.6l's and they both acted up as soon as i changed plugs, so i recommend staying with the motorcraft, thin wire, platnium plug called for under your hood. i've tried autolite dbl, and single platnium, and the bosch dble plat and the trucks rejected all three "quickly" to the tune of random missfires, ignition ping, hesitation and surgeing at constant speeds. and keep the boxes and reciepts just in case.

 

Stick with Motorcraft. Do a search on Ebay for "HilisBestDeals". He sells Motorcraft plugs for half of what the dealer sells them for. In either case, STAY AWAY from Bosch. If you must use an aftermarket plug, get a set of NGK non plats. Very inexpensive but work very well.

 

I have the same truck a '99 4.6 V8 and last year I got the plug/wire/coil pack combo from Troyer Performance. It worked great. It comes with Accel wires, MSD coils and Denso Iridium plugs. It made a huge improvement in power, mileage and driveability. They are a bit pricey but IMHO well worth it.

 

What kind of pricey are we talking about? I'm a poor (not really) highschool student who is supposed to be saving for college ... but it's sooooooo much better to spend my money on my truck

 

Check out Troyerperformance.com and look for the ignition upgrade kit. I think it was around $300. Just work a couple extra weekends at the job and you'll be good to go.

 

I just changed the plugs I replaced about 2 months ago in my 99 4.6, they were Bosch platinums, the one in cly 7 had a cracked insulator and caused the truck to misfire and throw codes. I also chose the motorcraft plugs and the truck runs great.

 

How much 'power' and fuel economy did you gain? Just curious as $300 is a bunch of gas to burn up to ,make it worth it to me (too many other irons in the fire right now). Plust I just changed the plugs in my Screw...do NOT want to do that again anytime soon.

 

Like Headbanger, I would suggest the ignition upgrade package from Troyers.

This is the first Ive ever heard of someone having problems with with Autolite plugs. Normally, the only plugs that will work in these trucks are MotorCraft and AutoLight.

I have Autolite double platinum in mine and havent had a problem with them.
I dunno.

 

Did the motorcraft set last month, and let me tell ya those are hard buggers to get out.

Adrianspeeder

 

Best thing I did was buy a 10" extention for my 3/8s drive sockets. A small cheater pipe would have been nice too. LOL Once I got the COPs off it was fairly simple. Don't forget to blow the trash out of the plug recesses.

 

Yeah, your going to need as many knuckles and extensions as you can get, your gonna need them.

Took me like 2 hrs. the first and only time I did it.

The farthest back passengers one is the hardest to get, and they all slant back into the firewall-talk about a dumb design if I ever saw one

 

I can't say for sure how much power increase I got from the TP ignition upgrade, maybe 5-10 HP, but whatever it is, its noticeable. I'm sure some of it is just regained power that was lost due to worn out coils and broken down wires. As for mileage I'm guessing I got a 1 mpg improvement. You got to change these coils/plugs/wires anyways as normal maintenance, why not get a little extra seat of the pants improvement while your at it.

 

Cause I just finished putting plugs in mine and I don't want to do that again anytime soon.