4.6 Spark Plug Wires Routing? Advice!


New Member
Jul 25, 2006
I have heard from several people that 4.6 spark plugs wire have to be routed a special way. Example #2 can't be next to #4. I wasn't told what order they have to be in so I wasn't for sure if it was true. I just got a 98 GT and I am changing the plugs and wires and just wanted to make sure.

Also is there anyway to change the plugs without pulling the fuel rails?

Thanks guys.
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Pulling the fuel rails, are u insane?? No don't do that. When doing plugs and wires do them one at a time, and start from longest to shortest. In doing so clean the plug wells out with compressed air.
Yes I am talking about from the coil packs to the plugs. The is separate from the firing order of course. This could be a myth as well. I am just wondering if anybody has heard anything like this. One of the guys I heard this from is a Ford Tech so that makes me wonder. Supposedy if certain wires are next to each other (say #2 and #4) then they will arch with each other. You would have to separate #2 and #4 by putting #1 or #3 between them. I don't know.

As far as the plugs I have got #4 out (pain in the butt) now I am having problems with the rest. Need a good solution, hopefully without using a u-joint socket.

Thanks guys.
Take off your fuel rails? Get a long extension (i think i use a 12" and sometime add a 6" to it) and a swivel (i dont think you even need one) but if you cant get them out without taking off your fuel rail you should let someone else do it for you.
Never knew you couldn't put one by a certain other... I've always just laid them down in the looms where they are in a ascending order of length. They seem to route only one way. As far as touching they seem to no matter what where they cross over.

My MSDs with my supercharger...



My FRPP on my NA...


As far as changing plugs... no need to remove anything except whatever is covering the last plug on the driver's side. A good swivel head attachment, socket with duct tape on your socket to extension will help tremendously.


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Here is what I was talking about. I came across this in another thread. This is what they stated:

"When a spark plug fires, it creates a great deal of radio frequency interference (RFI). Uncontrolled, this can show up as static in the radio or other electronic devices, or much more seriously, in electronic ignitions, fuel injection, and engine management systems. This interference with EFI and engine management systems can cause "cross talk" between wiring harnesses resulting in poor running, misfiring and decreased performance."

"...many manufacturers recommend wires be replaced when the resistance exceeds 20k ohm/meter. This does not leave much margin for wear when the wire may only meet original standards at the very early stages of its life."

This doesn't tell you if you should rout them a certain way though.
Aren't all wires covered in rubber which is an insulator so they should never spark across unless there is a cut in the rubber.

As far as some RF being created some how, if you are worried you can buy some 3M copper EFI tape that will block almost any RF, we use that tape to seal RF leaks in the screen rooms at work.

just put the wires back were they came off at and as for the plugs no the fuel rails dont need to come off use a 3/8 swivel after the plug socket and a 6in or longer extension. i changed my plugs only, tuesday nite 3hrs. after having a tooth pulled, it took me all of about 10mins incuding the one on the pass. rear so go for it