My truck started idling / running rough this morning. It kind shakes a bit and when I give it a little gas it shakes quite a bit more and is slow to get to speed. I have 2001 SuperCrew 5.4 with 43k miles. I have never changed the plugs or fuel filter. This lasted about 5 minutes, until I stopped at work, after running fine the previous 25 minutes. Also, it did this once about a week ago for about 20 seconds. I thought it might have been some bad gas. I have since filled up at a different station. Any suggestions to solve this would be quite helpful. Thank You - LouScrew

 

Lou,

So a Search for sparkplug and ignition coil.

Several folks have had coil failures, usually the rearmost on the passenger side, and some have had plug failures, but 43K is a bit early for that.

 

since it is so sporadic and not consistant I would guess it is just a sensor that got hung up for a bit.

if you are making a lot of short trips it can have a similar affect as you are describing when the 02 sensors get wet from the large amount of water that is created during the cold combustion process which doesn't get burned off during the short trips.

also check your coolant level. if it is a little low the coolant temp sensor which basically runs the whole show dosen't get fully covered in coolant can mess a bunch of operations up.

 

hcmq,pushrod,
I went and ran it at lunch. It ran perfect. I think I am going to take by mechanic today after work. I don't want to take any chances. Thank You for you input - LouScrew

 

hey let me know what it was mine did the same thing this morning. thanks

 

I took to my mechanic after work. He put on his diagnostic machine and couldn't find anything wrong. He said that it is probably some kind of sensor but it didn't show up in the diagostics because it didn't last long enough for the check engine light to come on and he needs the check engine light to come on in order to determine which sensor needs replacing. He said it is more likely to happen during high humdity, which it was both times this has happened. He said to keep driving and if/when it happens bring it back in. He said it won't hurt anything and usually corrects itself as soon as the moisture disipates but whenever the check engine light comes on, he will replace the bad sensor. He said it is somewhat commen in Fords. Hope this helps. - LouScrew

 

codes are not a guide for what sensors to replace. the codes are only a place to start your diagnosis.

for example if a code says that an 02 sensor is bad you need to find out what made it go bad. (unless of course you are way over due to change the sensor anyway)

 

 

I have a 2001 F150 Supercab 4x4 with a 5.4L EFI. I had just had a coil replaced at the dealer and on the way home, the truck would miss @ between 40 - 45 MPH under acceleration. It did this about 3 times before I got home. After that it was fine until yesterday and it did it again twice. It doesn't happen for a long period and only while accelerating at 40-45 MPH. It'll shake for as long as I'm accelerating and stop if I let off. I've got 52,000 miles on it. It may be the same problem because it won't happen long enough to put the check engine light on. Any ideas

 

Hey, i have the same type of problem. Mine u can go out and start early before i leave for work, and the thing sometimes starts up fine, and other times the thing wont idle to even save ur neck. It will sit and idle up and down like its supposed to, to get warmed. But other times it overloads like its going to warm up, but like the thing will sit and die almost and then idle up, then back down and almost die again, and it will do it for like 5-10 minutes. And its only getting worse, and more often. So, i think that my trouble is in the IAC(Idle Air Control). I drive a 1991 F150 regular cab, 8' bed and 5.0 302. Maybe this will help u, and if not, maybe someone can give me an answer for mine.

 

Well finally got it diagnsed and fixed. It was the number 3 coil and bad spark plug. Had them change all the plugs and the coil. I now have 45 k on my truck. I hope this can help someone else in the future - LouScrew

 

I've been having the same problems with my '01 Screw 5.4 Took it to the dealership last week after it started running rough and losing power and they claimed it was the #5 coil. They wanted over $300 to replace it, when the part is just over $50.
I replaced the #5 coil just yesterday along with the spark plug and it ran fine for about 5 minutes and then started running rough and felt like it was missing again...
Is there any secret to replacing the coil or spark plug? I did it twice just to be sure.

 

lou make sure you check the heater hose above the coils on the pass side of the engine compartment. it will seap/drip on the two coils below it and cause the problem you had.

i have seen posts on here where people have replaced 2-3 coils and their mechanic coulodn't figure out why!!

remove the stock pinch type clamp, push the hose over the rib on the metal hose and then use a screw type hose clamp.

 

I had the same misfiring problem. I hooked it up yo my obd-2 reader and it came back that cylinder #5 was missfiring. I then replaced the plug and coil (5.4). A week later same problem but Cylinder 7. I did not want to buy another coil so I checked this one better. I took the coil off pulled the rubber boot off there is a spring that is about 3 inches long that connects the coil to the sparkplug. There was corrision around the coil to spring connection. I took the spring off and cleaned the connection. Next I put some dielectic grease on the connection and reconnected the spring. I hooked everything back up and no more missfire. I hope this may help some else from paying for a new coil.