Problem with my '05 Expedition & need your help! UPDATE 5/11

[ContryboyFE]

To start off I've been to the exp forms
1 they are hard to navigate.
2 their ads/pop ups are annoying
3 the adds are border line inappropriate
4 they don't seem to me to be ... I Don't know how to put it nicely ...

I bought my wife an '05 Expedition about 4 years ago with about 96000 on it. We had. The dealer replace the plugs & we did the coils @ about 110000. We are currently at 166000 & that's all I've had to do outside of routine maintenance.

Last weekend it started to miss fire & threw the. Code for a general miss on cyl 7 then 3. So I replaced both plugs & warrentied out both coils & replaced the fuel filter just to be safe. -it was almost time anyway- It is running better but it is still stumbling under hard exceleration (especially in O/D) & the check engine light comes on & flashes but dosent stay on. The best I have found yet is that the light means its an emissions issue. That dosent narrow it down that far.

At this point I'm not too sure where to go next.


I miss my bump!!!!!!

[sargentrs]

Check your air hose from the air cleaner box to the throttle body for tears or leaks. Also check that the top of the air box is clamped down good. These new engines don't like it when you interrupt their air flow or vacuum.

[ContryboyFE]

The air box is bolted to the tb like the old carb set ups. But ill definetly. Check for leaks

[chad67]

I went through this exact same issue with my wife's minivan and it was the plug wires. I replaced them in January to fix the exact issue you describe. It came back 2 days later, so I changed the plugs and coil pack. It was a little better but not quite right. Checking everything lead me nowhere. It was driveable, but annoying. She would drive it and when it was especially bad, I would check everything I could think of. Out of desperation, I got another set of plug wires. Fixed it! I hope it doesn't go through a set every 2 months, but I got a better (read: more expensive) so hopefully it will stay together longer.

[chad67]

I looked online and I see that you have coil on plugs. It may be the boots that go from coil to plug.

[ContryboyFE]

It is a coil over plug set up. 1 coil per cyl No wires

[chad67]

I've never worked on the coil on plug set up, are there any wires inside the boot that goes from the coil to plug? I see Oreilly sells them. I read in a magazine where someone was upgrading their newer 'Stang and had the same issues you have and apparently there is a very specific proceedure for torquing the spark plugs. They had to follow it exactly to get it to run right.

[ContryboyFE]

Inside the boot of the coil is a "spring" that transfers the energy.
I have never read or heard of a specific order to torquing the plugs but getting the proper torque is vital. That's is what was wrong with 7. It was loose & blowing past the plug & killed the coil.

Specifically what's happening:

The truck has had a slight erratic none specific miss from day one. It has always reminded me of my ol 360. Even with brand new plugs, coils, fuel & air filters.
It starts & idals -sp error- fine. Take off is smooth. As long as I do not get on it. Once it shifts into o/d it is more pronounced. If I do accelerate too hard in any gear it starts to stumble & sputter. It is almost like I've hit a rev limited. The computer senses an issue sets off the light on he dash & shuts down the engine to a safe mode or something & I loose power. Now if I stay on it even slightly it stays in this "safe mode" but if I get out of it & wait it goes back to "normal mode". Once back if I stay out of it it will run alright. -i just can't say good- At this point we can start the process over.

[chad67]

Yep, that's what the wife's turd-er-minivan was doing. It would cruise OK, but try to go up a hill and when you gave it throttle it would sputter and fall on its face. I would check on the plug torque proceedure and check the inner workings of the plug boots. If the issue has been around for a while and the boots have never been changed, I would definitely look there. What confused me was the way it would run OK at lower throttle settings, I can't explain why bad plug wires were throttle sensitive, but I do know changing them fixed the problem.

[ContryboyFE]

Plugs & coils were done at about the same time. The plugs are hovering around 50k & the coils were done a couple months later. I dropped over $1200 in a matter of a few months on that tune up. They told me they would be good for around 100k. They haven't made it half that.
My wife & I talked it over & we are going to purchase the remaining 6 plugs over the next few weeks. $13/plug & $45/coil so do the math. The coils are lifetime warranty through a big name parts store so if they are bad they will swap them out for me.

It is crazy how it is acting. It has a weekend worrior shade tree mechanic stumped.

That's why I love this site. We are passonate about our ol trucks & willing to lend a hand on the "newer" stuff too.

[thejunkman]

I've heard of this a lot on 5.4l tritons. And I experienced it with a 2002 f250 super duty I was going to buy. It was one of the COPs. I can't remember what was causing it, but one particular COP kept failing, I think due to improper voltage. It would stumble under load and then the shudder would disappear. It was especially noticeable on hills, and almost un-driveable on wet days.

edit*
Saw this on a good write-up on COPs :

"A variety of aftermarket tool suppliers sell inductive pickup adapters that can be attached directly to the coils on various COP systems to gather secondary ignition information. Most of these adapters cost less than $50 each and allow you to observe secondary ignition data for each coil on a scope or scan tool that can display ignition patterns. In most applications, the coils do not have to be removed to connect the adapter (it fits over the top of the coil and uses induction to pick up coil voltage).

COP adapters are available for various BMW models, Chrysler 2.7L, 3.2L and 3.5L engines (Dodge Intrepid, Chrysler Concorde LHS and 300M), Ford 3.4L Taurus SHO, 4.6L Town Car and Mark VIII, Mustang, Crown Victoria and Grand Marquis, and F-Series and E-Series trucks with 5.4L and 6.8L engines, Acura SLX, Honda Passport, Isuzu Amigo, Rodeo and Trooper, Mercedes with M112 and M113 engines, Toyota and Lexus with with 1UZ-FE and 2UZ-FE engines, Audi A4 1.8L turbo and A8 4.2L, Volkswagen Passat 1.8L turbo, Volvo 960 and 9000.

Another handy tool that can be used to quickly find a dead or misbehaving coil is an inductive ignition probe. This hand-held tool sells for less than $100 and is simple to use. It has an inductive paddle that is placed over the coil to detect coil activity. A super bright LED strobe flashes every time the coil fires and produces sufficient kV. A green indicator LED also flashes when the presence of adequate spark duration is detected. This tool eliminates the need to back-probe connectors and to disassemble and test each coil at its connectors."

the whole article is here... http://www.autotap.com/techlibrary/unde ... ystems.asp

[tac]

Did you check the codes after this? I think its saves them even if the CEL goes out. Check the connector on top of the COP, the tab that locks them on can break and connector will back out. Cylinder misfires are detected by inconsistent engine speed so if it alway the same cylinder may want to look at the injector. Random misfires can be caused by intake air leaks, or even loose or faulty cam/crank sensors.

[ContryboyFE]

Cam & crank sensors! I knew their was some something I was forgetting.
I haven't had a chance to do anything since sunday. Gotta love o/t. My plan is to check for leaks & track down all of those sensors this week & work on it sat/sun.
Junkman.
That those tools are thay an equivelant to a timing light? I've never heard or seen one.

[1972hiboy]

the only time I lost a crank sensor on a 5.4 it stalled out completely and wouldnt restart. Ive had a couple vans with the 5.4 do the under load miss as you have described. I apologize I havent re-read the entire thread. but have you changed out the plugs and coils in the offending cylinders when you did get a code for them? Both times I have this kind of stumble or miss was due to a defective coil and or plug.

[Ranchero50]

Ditto, pull all the coil packs off and smell the boots. You can smell the ones that are not firing well. Tweak the ends of the springs and make sure the boots don't have oil or coolant on them (brake clean everything). Worse on wet days says it all.