How to replace your 4.6L & 5.4L spark plugs - Page 2

GA boy · #16 (**permalink**) 09-10-2003, 08:38 AM

Don't know the exact conditions of your boots getting stuck, but that reminded me of another tip. A set of boot pliars (my name for them) are great for removing stubborn boots. When removing the boots, you have to pull and twist. Sometimes this is not that easy to do, but you have to twist more than you pull. Get a small tube of the anti seize lube and be sure to use it on the installation.

These wires are incredibly expensive. They should be handled with care and caution.

HotF150 · #17 (**permalink**) 09-13-2003, 12:14 PM

I don't know if this would work for the COP models, but for my 4.6L that has just a boot and wire on the plug, I found that wrapping a length of twine around the top of the boot and giving it a good pull helped in getting the boot off of the plug. It even worked on the #4 - popped right off after I'd already spent about 30 minutes trying to twist it off the plug.

This is a great thread!

pro3qtr · #18 (**permalink**) 09-21-2003, 02:21 AM

A good rule of thumb is to check the plugs at 50K

My stock plugs where wasted at 45K !!!

Check your heater hose above #4 plug, most all are LOOSE!!

My #4 was change before and the second plug was rusted up !! From the hose leaking.

GrandBlanc · #19 (**permalink**) 09-29-2003, 01:16 PM

If your looking at the 5.4L engine from the front of the vehicle, how are the coils numbered? Odds on left evens on right? Any help would be cool.

Racerguy · #20 (**permalink**) 09-29-2003, 08:49 PM

The furthest ahead cylinder is #1, the front one on the passenger's side. It is 1,2,3,4 on the passenger side, 5,6,7,8 on the driver's side.

macgyvr · #21 (**permalink**) 11-21-2003, 01:54 AM

I'm bringing this back up to the top as I printed this thread for reference as I changed the spark plugs on my truck tonight. This thread IS a MUST read for anyone getting ready to change their plugs.

The article is printed here: http://www.ford-trucks.com/articles/2003/10.php

but this thread still has more info than what got included in the article. you'll have to excused me as I got the spark plugs done and then have drank until i can barely see/type straight....

The number 7 and 8 are the worst. I cussed until i couldn't cuss no more at them. You either need a socket wrench that has a flex head or a 7mm gear wrench for those damn COP bolts. That number 7 is an SOB!!!!!

The spark plug socket with the four inch extention then the universal then a longer extension worked perfect for me in getting the spark plugs out...

I had a lot of gunk in mine and used a shop vac w/ a piece of heater hose duct taped to the end to suck the crap out of the hole before took the spark plug out, this helped termenously in getting the gunk out before you put the new spark plug back in.

After reading and rereading this thread, since this is the first time i was working on the f150 5.4 motor, it took me 1.5 hours to do the pass side and 2 hours to do the drivers side. i'm pretty good with the wrenches and have pulled serveral motors but these are the most time consuming and makin ya cuss like a sailor spark plugs that i have ever run across.....

even after all that at 60k, i'm ready to do them again whenever i managed to get 120k on the motor.....

mac 'put the reccomened platium motocraft plugs in' gyvr

PaulC · #22 (**permalink**) 01-19-2004, 03:07 PM

Swapping a suspected bad COP with a known good one sounds like a good diagnostic method to me. If the misfire migrates to the cylinder with the old #4 COP, you've got it.

BTW, the most common reason for demise of the COP on the #4 cylinder is leaking antifreeze from the heater hoses poised over that section of the engine. I suggest that you ensure that you don't have any antifreeze leaks in that area before you swap/replace COPS.

richkrik · #23 (**permalink**) 02-28-2004, 07:01 PM

Well, I am now a memeber of the "replaced the plugs in my F150 5.4" club. It wasn't nearly as bad as I thought after reading this thread. If you are going to do it, here are some good hints, besides what you read here:
--While it may be possible to pull the COPS without removing the injector rail, I can't imagine not doing it. It's so simple. A couple of screws, coupla grunts, and up she comes. Remember to relieve fuel pressure before you do this. Autozone has a $30 fuel pressure meter with a relief valve/hose to drain fuel in rail. Also remember to plug injectors and rail when blowing all the crud out of the plug hole.
--I taped some vacuum hose on my blow gun to get the dirt out of the plug holes. Very surprised at the dirt/etc. in there.
--I used more vacuum hose to put on the end of the new plugs to use as a device to start the plugs into the threads. Very handy.
--The Denso Iridiums I bought ALL had to be regapped to .050, their claims to be pregapped notwithstanding. Make sure you check yours.
--Torqued the plugs at 14ft/lbs.
--I removed tires and lowered my truck on to a coupla blocks of wood to get my big belly over the front of engine compartment. When I raise it six inches in the future, I'll have to do this AND use a stool.
--It REALLY helps to have LOTS of esxtension bars, and especially a locking extension bar to hold your plug socket, so it doesn't come off when pulling it out.
--Only had one boot get stuck on me, got it out with some really long nosed pliers. Won't happen again as I used dielectric grease on the new ones.

Hope this helps, and thanks to everyone for all the good ideas here. I won't be nearly as hesitant next time.

brownjc · #24 (**permalink**) 03-14-2004, 07:04 AM

This thread on changing spark plugs has been very informative. My '99 has 112,000 miles. I changed plugs last year, but I am wondering about wires and COP's. I think they are original. Should these be changed out on a truck with this mileage? Truck is running rough and "Service Engine Soon" light has come on. I believe the trouble is #4 spark plug is either loose or is not sparking for some reason.
Thanks

Racerguy · #25 (**permalink**) 03-14-2004, 12:01 PM

Have you had your truck scanned to see what code caused the light to come on? If it is misifre related it will tell you which cylinder the problem is.
What size engine in your truck? The 4.6 has plug wires, the 5.4 has COPs. COP stands for Coil On Plug. Each spark plug has it's own coil sitting on top of it and no spark plug wires.

brownjc · #26 (**permalink**) 03-14-2004, 06:39 PM

Racerguy - thanks for the response - no I haven't had the computer scanned yet. I have the 4.6 engine, so now I understand I don't have COPs. I took the #4 plug wire off, made sure the spark plug was tight, cleaned the plug boot and reinstalled. The truck is running smooth now. So now my two questions are:

1. With 112,000 miles, should I replace plug wires? I'm not familiar with these newfangled ignition systems with no distributor cap/rotor to replace!

2. If the problem is fixed, will the "Service Engine Soon" light go out by itself?

3. If not, any recommendation for a ceap handheld unit I can buy to read/reset my own codes?

Thanks - your responses on this board have been invaluable.

Racerguy · #27 (**permalink**) 03-15-2004, 12:03 AM

You're welcome

I would think that replacing the plug wires would be a good idea. The stock wires are good for a long time but sometimes a bad plug can be hard on a wire as it stresses the wire more if the spark has a problem going where it should go. The plug wires on these are a bit of a pain to replace but if you do one at a time you'll be ok.
The Check Engine light will go out eventually but you can clear the code and turn the light out by disconnecting a battery terminal for 10 minutes. If you do that and the light comes back you know you've got a problem that you should get checked. if you have an Autozone there apparrently they will scan the system for free. If you do get it scanned make sure you write down the code number and not just the description. If you post a code on here we can help you get it figured out.
As for a cheap scan tool I dont have any good suggestions but if you look around in the forum you'll find lots of opinions on what ones are good.

scprjamie · #28 (**permalink**) 03-15-2004, 08:59 PM

Have a 97' F-250 with 160,000mi with the original plugs. Lucky so far I guess. What,s the worst thing that could happen as a result of not changing them?? No idle problems so I assume keep running them until I have a problem. Thanx in advance for your reply.

Racerguy · #29 (**permalink**) 03-16-2004, 12:56 AM

You can't always feel a slight misfire but your old plugs might be doing that which will hurt gas mileage some. Old plugs that are worn can have very big gaps for the spark to jump which puts extra stress on the plug wires and/or coils.
Even if it feels like it's running ok I think it will probably run better after you replace them.

deckofwood2002 · #30 (**permalink**) 03-16-2004, 03:56 AM

i change plugs on the 4.6,5.4 and 6.8l's all the time but fortunately the engine is on a engine cart due to i work in a dyno lab.what i found very very useful are the locking extensions.it's quicker and you don't lose your socket in the head.although the 3v versions of the modualar motor you need a 9/16'' socket to remove them,so what i did is remove the rubber boot from the inside of an extra 5/8'' socket and stuffed it into the 9/16'' socket.WORKS GREAT.