missin - Diesel Forum

justinrpalmer · 04-23-2003, 12:39 PM

my wife's expedition is acting funny when you drive it down the road. [img]/ubbthreads/images/graemlins/frown.gif[/img]
Its kinda acting like its missin. It idles fine and accel. fine but just driving at a constant speed it starts acting up. I thought it was just bad gas so i put a new fuel filter on it and put in some fuel injector cleaner but problem still there. Any suggestion? thanks
Justin

Birdman · 04-23-2003, 12:43 PM

Maybe its time for a tune-up. [img]/ubbthreads/images/graemlins/shrug.gif[/img] Roger

bajarunner · 04-23-2003, 03:53 PM

Been a while since I was diagnosing things, but a couple of suggestions:

Figue out if the miss is a particular cylinder, or if is misses due to a fuel problem that could hit any cylinder (with TBI, this is MPFI, right?). What kind of ignition on it? Coil over plug, or does it have wires? If wires you can pull the boots with insulated pliers (special spark plug boot tool) and when you get the bad one the RPM won't change when you disconnect it. Then check to be sure it is sparking, and look closely at the plug for cracks, burnt electrode, buildup, etc.

I would also check the fuel pressure, low pressure will make it miss. HTH

Rob

ohski · 04-23-2003, 10:12 PM

Do you run a K&N on the EX? If you do the Mass Air Sensor could be dirty... the oil from the filter gets on it... Had to clean mine on the Ranger every 15,000 miles or so.

outpost22 · 04-24-2003, 10:14 PM

If you've done any recent motor work, it's possible you may have rerouted an ignition wire (?), and it could be rubbed or frayed enough to "arc" to a metal component. My G*C used to do this when it warmed up and took 2 months to find. Also, a loose ground wire is a possiblity.

dadomin8r · 04-25-2003, 12:04 AM

OOOOOHHHHHH my time to put two cents on Ford's expeditions and the 5.4L. I had a 98 with a 5.4. about 70k miles and the thing sounded like it had an exhaust leak. My lazy butt didn't fix it right away and at 80k the spark plug in the #3 (it's been a while i think it was the #3) blew out of the head along with the threads. I took it to the local mechanic (mistake 1 that I will never make again, take it to FORD, those guys don't invest in the tools it takes to fix the new motors) and he put a solid helicoil in it (Cheap way to go that ford won't do). The damn thing still missed every once in a while.......long story short, it took a lot of money at 3 dealerships and a lot of cursing at the local mech, to find out that the missing was a tear in the coil pack boot. Even when they put a new boot on it would tear, because you have to flex it around the fuel rail. The rubber (whatever it is) is SO cheap, it tears putting the thing in. The tear causes it to arc to the head. It is a very common problem in the expeditions especially but in a lot of 5.4L motors as well.

Ford went with an aluminum head and used a plug with half the threads. Common sense tells you that this isn't the wisest choice, but the real problem is on Ford's assembly line.

Take it to ford and have them check which cylinder it is (hard when the miss is intermittent) and check the coil pack boot for a tear or test the coil pack itself. You can't really check which cylinder it is w/o their $$$$$$$$ machine. [img]/ubbthreads/images/graemlins/shocked.gif[/img]

robsd · 04-25-2003, 12:44 PM

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Maybe its time for a tune-up. [img]/ubbthreads/images/graemlins/shrug.gif[/img] Roger

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OH KNOW ANOTHER POKE!!! Oh Roger you got us good man. Well at least we don't RAVE!!! about wearing little rubber gloves at the fuel pump. I thought every diesel owner LOVED and LIVED for that smell. Some even say their wife loves the smell.

[img]/ubbthreads/images/graemlins/eek.gif[/img] [img]/ubbthreads/images/graemlins/eek.gif[/img]

Birdman · 04-25-2003, 02:09 PM

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Quote:
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Maybe its time for a tune-up. Roger

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OH KNOW ANOTHER POKE!!! Oh Roger you got us good man. Well at least we don't RAVE!!! about wearing little rubber gloves at the fuel pump. I thought every diesel owner LOVED and LIVED for that smell. Some even say their wife loves the smell.

[/ QUOTE ]

Gee it only took you 2 days to catch that. [img]/ubbthreads/images/graemlins/eek.gif[/img] What would I expect from someone that wastes money on spark plugs. [img]/ubbthreads/images/graemlins/biggrin.gif[/img]

robsd · 04-25-2003, 05:05 PM

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Gee it only took you 2 days to catch that. [img]/ubbthreads/images/graemlins/eek.gif[/img] What would I expect from someone that wastes money on spark plugs. [img]/ubbthreads/images/graemlins/biggrin.gif[/img]

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Oh man....another stab right into the heart. You guys just kill us with your wit. Actually I resisted responding because I didn't think it was worth the time. Then I got some free time.

But gee I must be like you diesel guys because I " waited" to respond. I mean you guys should be use to " waiting" all the time because you must " wait" for your glow plugs to heat up and the " wait" light to go off. Boy I bet yall freak out when crossing a street and the " wait " light comes on. I guess yall just stop in the middle of the road until the " WAIT " light goes off.

Wonder if that's like a secret zombie code. Like your at a PSD conference and somebody holds up a WAIT sign and everyone freezes like Zeta-Jones just walked into the room with a phone in her hand.

Oh and the waste money on spark plugs is another HUGE put down....but wait, I think my 10 plugs cost about the same as a couple fuel filters for a PSD. Not to mention the same a as a few boxes of those latex gloves yall use for fueling. I just bust a gutt laughing thinking about some tough looking PSD dude pulling up to the pump all dirty and everything with a 15,000# trailer (overloaded of course) full of hay then breaking out a box of latex gloves to keep the diesel off his hands. Now put that in your minds eye and just try not to laugh. [img]/ubbthreads/images/graemlins/grin.gif[/img] [img]/ubbthreads/images/graemlins/grin.gif[/img]

Rob [img]/ubbthreads/images/graemlins/grin.gif[/img] [img]/ubbthreads/images/graemlins/grin.gif[/img]

 WAIT....just remember we're having fun here. [img]/ubbthreads/images/graemlins/biggrin.gif[/img]

Birdman · 04-25-2003, 06:06 PM

[ QUOTE ]
I just bust a gutt laughing thinking about some tough looking PSD dude pulling up to the pump all dirty and everything with a 15,000# trailer (overloaded of course) full of hay then breaking out a box of latex gloves to keep the diesel off his hands. Now put that in your minds eye and just try not to laugh.

[/ QUOTE ]
Can't do it, I guess I'll agree with you on that one [img]/ubbthreads/images/graemlins/biggrin.gif[/img].
Last night I had to wait for a V-10 to get out of my way going up a small hill, but he was loaded down (3 bags of groceries) [img]/ubbthreads/images/graemlins/eek.gif[/img] [img]/ubbthreads/images/graemlins/biggrin.gif[/img] [img]/ubbthreads/images/graemlins/biggrin.gif[/img]