Check Engine problems....98 Expedition 5.4L
Fleet Mechanic
Joined: May 2005
Posts: 1,567
Likes: 3
From: Chattanooga
Ok I love this forum but never come to the gasser side.....need info on #4. Mine coded cause the idiot husband (me) washed the underside of the engine compartment. Should just clean the connectors with brake clean but is number 4 def pass side rear? My book only goes to 00 and mine is 99 for info on the coils. Not too fam with 5.4 only 7.3 diesel. Thanks for any assistance
Freshman User
Joined: Jun 2006
Posts: 48
Likes: 0
From: Jacksonville, AL
I'm no auto mechanic and I lean towards electronics but one thing I've learned over 24+ years in equipment troubleshooting is that the silliest (I should have checked the $.50 part first) thing is what usually gets you. It's interesting to note that this principal carries over to the automotive world.
Just an observation.
P.S. I'm learning a ton on this site.
Thanks
Just an observation.
P.S. I'm learning a ton on this site.
Thanks
Tuned
Joined: Sep 2003
Posts: 296
Likes: 0
From: north carolina
#4 plug is definititely rear most plug on the passenger side on the 5.4 Triton. COPS are held down by a small bolt (no retainer clip). The connector attaching to each COP releases with a pressure clip on the very end (wire end) of the connector. If you grap the connector anywhere other than the very end, it won't release and you'll get very frustrated.
Posting Guru
Joined: Jun 2006
Posts: 1,590
Likes: 1
Yes, #4 plug, is one of the hardest to get to. Look at the #1 and you'll know what you have to do. Mine went bad 2x. It now takes me about 10 minutes to change the coil and plug. The coolant leak is notorious on these. Lucky for me I bought my cop from advance auto and they have lifetime warranty. I just traded it out, and got a new one.
New User
Joined: Feb 2005
Posts: 18
Likes: 0
finnally got my 98 exxpy fixed. i came here and saw the guy write about wiring issues and i went and took a look at mine. I came accross a rub on the wire that connects to the COP. well this rub wore through the wire itself and was grounding out before it got to the COP. Replaced the wire runs fine. gotta say thanks didnt really think about that.
But now onto a new issue. After sitting for a year the brakes arent what they should be. There is almost no power in the peddle. I bled the system and put new brake fluid in but the brake doesnt build up, and you almost have to press it to the floor. If i remember right there is a valve that controls the vacuum for the brake power booster or it could be the power booster itself which should i try to replace first. And is there a way to check this? If you have any other idea's im open for it. I have limited knowledge on this power booster and valve.
My expedition runs like a dream now but stops like a nightmare.
Thanks for the previous help
Buzzman
But now onto a new issue. After sitting for a year the brakes arent what they should be. There is almost no power in the peddle. I bled the system and put new brake fluid in but the brake doesnt build up, and you almost have to press it to the floor. If i remember right there is a valve that controls the vacuum for the brake power booster or it could be the power booster itself which should i try to replace first. And is there a way to check this? If you have any other idea's im open for it. I have limited knowledge on this power booster and valve.
My expedition runs like a dream now but stops like a nightmare.
Thanks for the previous help
Buzzman
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Posting Guru
Joined: Jun 2006
Posts: 1,590
Likes: 1
Originally Posted by Buzzman222
finnally got my 98 exxpy fixed. i came here and saw the guy write about wiring issues and i went and took a look at mine. I came accross a rub on the wire that connects to the COP. well this rub wore through the wire itself and was grounding out before it got to the COP. Replaced the wire runs fine. gotta say thanks didnt really think about that.
But now onto a new issue. After sitting for a year the brakes arent what they should be. There is almost no power in the peddle. I bled the system and put new brake fluid in but the brake doesnt build up, and you almost have to press it to the floor. If i remember right there is a valve that controls the vacuum for the brake power booster or it could be the power booster itself which should i try to replace first. And is there a way to check this? If you have any other idea's im open for it. I have limited knowledge on this power booster and valve.
My expedition runs like a dream now but stops like a nightmare.
Thanks for the previous help
Buzzman
But now onto a new issue. After sitting for a year the brakes arent what they should be. There is almost no power in the peddle. I bled the system and put new brake fluid in but the brake doesnt build up, and you almost have to press it to the floor. If i remember right there is a valve that controls the vacuum for the brake power booster or it could be the power booster itself which should i try to replace first. And is there a way to check this? If you have any other idea's im open for it. I have limited knowledge on this power booster and valve.
My expedition runs like a dream now but stops like a nightmare.
Thanks for the previous help
Buzzman
Have someone pump the brakes until they are stiff, and then hold their foot on the brake pedal. Release the bleeder valve and their foot should press the pedal to the floor or almost to the floor. Keep their foot there, and tighten the bleeder valve. Then have them do it again, and again, and again, until you are certain that there is no more air in that cylinder. Move to the next cylinder as stated above. Check the Master cylinder after each cylinder or more often if you are bleeding alot of fluid out. Its a good idea to do this anyway, the longer your fluid stays in the system, especially after it sits, the more chance you'll have of the fluid absorbing water and then rusting through your brake lines!!!!
Last edited by 99ExpyProblems; Jun 29, 2006 at 05:54 PM.
Hotshot
Joined: Jan 2004
Posts: 19,768
Likes: 1,082
From: St Louis
An easier one-person method to simply put an inch or so of fluid into the jar, make certain the hose end is submerged, then open the bleeder and pump away making certain the reservoir never sucks air.
After several pumps, the air is all expelled from the hose and cannot be sucked back into the lines as long as there is a good seal between the hose and the bleeder.
Close the bleeder and remove the hose. Move on to the nxt corner.
Steve
After several pumps, the air is all expelled from the hose and cannot be sucked back into the lines as long as there is a good seal between the hose and the bleeder.
Close the bleeder and remove the hose. Move on to the nxt corner.
Steve
Tuned
Joined: Sep 2003
Posts: 296
Likes: 0
From: north carolina
Kennedyford,
If I remember right, the pressure clip on the connector is on the bottom. Practice on the #1 or #5 COP since they're easiest to reach at the front of the engine. Then, you'll know what you're doing and what to feel for when dealing with the ones in the back under all the hoses and junk. Like I said, the release clip is at the very end (wire side) of the connector. If you grab it close to the terminal end, it'll never release and you'll swear its never coming off, then end up breaking the connector or something.
BTW, I always put a little dielectric grease on the terminal end of the COP connector when I re-install it. Doesn't take much moisture to corrode a terminal and cause a mis-fire.
If I remember right, the pressure clip on the connector is on the bottom. Practice on the #1 or #5 COP since they're easiest to reach at the front of the engine. Then, you'll know what you're doing and what to feel for when dealing with the ones in the back under all the hoses and junk. Like I said, the release clip is at the very end (wire side) of the connector. If you grab it close to the terminal end, it'll never release and you'll swear its never coming off, then end up breaking the connector or something.
BTW, I always put a little dielectric grease on the terminal end of the COP connector when I re-install it. Doesn't take much moisture to corrode a terminal and cause a mis-fire.
New User
Joined: Jul 2006
Posts: 2
Likes: 0
I'm interested in what the wiring problem was with #4 as my car has the same problem: P304 misfire engine code, swapped #4 with #1 and problem moved to #1 (P301 engine code), replaced COP on #1 (old #4) and ran fine for about 15 miles and then got P304 again.
Elder User
Joined: Sep 2006
Posts: 871
Likes: 0
Make sure you inspect the heater hose and pipe that sits above the #3 and #4 coils.. it tends to leak a little due to a loose clamp and eventually shorts out the coils.
Just thought I'd tell you before your new coil gets fried..
good luck
Just thought I'd tell you before your new coil gets fried..
good luck