Notices
1997 - 2006 Expedition & Navigator 1997 - 2002 and 2003 - 2006 Ford Expedition and Lincoln Navigator Discussion

5.4 Running Very Rough

Thread Tools
 
Search this Thread
 
Old Feb 27, 2012 | 01:58 PM
  #1  
Icefan71's Avatar
Icefan71
Thread Starter
|
Elder User
Joined: Feb 2005
Posts: 630
Likes: 1
From: Central PA
5.4 Running Very Rough

98 Expe EB 5.4 - Last week I changed out all the COP's. Noticed an improvement right away. It was slightly rough between 1200-1500 rpm before the change. Now that went away. Throttle response felt a bit better. Well last night the wife says its running real rough and the whole truck shakes when driving. Today I start it up and notice a rough idle and I took it for a drive and yes the truck shakes slightly when driving. It feels like one cylinder isn't firing. When I blew a spark plug a couple of years ago, the truck drove the same way. Its just not making the loud popping sound it made from not having a spark plug in the hole. I rechecked all the connections. All COP plugs are tight. All injector plugs are tight. I checked all the hoses where I had to squeeze my hands through to make sure I didn't crack or disconnect any. They are all good. For a few seconds I thought I smelled fuel while I was looking at the passenger side. I couldn't see any leaks. The smell went away, though. New COP's are Accel from Summit. There is no CEL so far. I don't know if I should take it for a drive until one pops up. I don't feel comfortable driving it. Any thoughts, suggestions?
 
Reply
Old Feb 27, 2012 | 02:08 PM
  #2  
Icefan71's Avatar
Icefan71
Thread Starter
|
Elder User
Joined: Feb 2005
Posts: 630
Likes: 1
From: Central PA
I unplugged 4 injectors 1 at a time to see if I noticed any changes. The engine still had the same rough idle each time. Maybe its there is some other problem.
 
Reply
Old Feb 27, 2012 | 03:11 PM
  #3  
alloro's Avatar
alloro
Fleet Owner
15 Year Member
Shutterbug
Liked
Loved
Joined: Apr 2008
Posts: 24,318
Likes: 5,128
From: 0,0,1
Club FTE Gold Member
Originally Posted by Icefan71
I unplugged 4 injectors 1 at a time to see if I noticed any changes.
What about the other 4?
 
Reply
Old Feb 27, 2012 | 04:01 PM
  #4  
Icefan71's Avatar
Icefan71
Thread Starter
|
Elder User
Joined: Feb 2005
Posts: 630
Likes: 1
From: Central PA
Not sure I understand what happened, but I did the rest of the injectors and didn't notice any change. Then I did the COP plugs 1 at a time and they each ran worse. I unplugged some of the vacuum hoses and those made it worse too. I'm just flying blind right now doing random things.
 
Reply
Old Feb 27, 2012 | 04:33 PM
  #5  
Icefan71's Avatar
Icefan71
Thread Starter
|
Elder User
Joined: Feb 2005
Posts: 630
Likes: 1
From: Central PA
OK, sometimes I'm a dummy. I was shutting the truck off as I unplugged each connection. then restarting every time. I just went out and checked each connection with the motor running the whole time. Every one got worse till I got to #8. That stayed the same. I pulled the new COP and put an old one back in. Truck sounds fine now. Only now the CEL came on. I'm guessing it was gonna come up because of the bad COP. I disconnected the battery. I'll hook it up in an hour and check it again.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ugh3012
1999 - 2016 Super Duty
14
May 15, 2015 09:14 PM
Dx2ry
2004 - 2008 F150
26
Jan 16, 2011 12:13 AM
ErikLydick
1999 - 2016 Super Duty
9
May 5, 2010 04:21 PM
Mr. Obvious
Modular V10 (6.8l)
7
Aug 2, 2008 03:26 PM
wezol5484
1997 - 2003 F150
3
Aug 29, 2005 04:00 PM




All times are GMT -5. The time now is 07:18 PM.

story-0
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-1
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-2
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-3
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-4
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-5
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-6
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-7
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-8
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-9
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE