HELP!! Misfire Cylinder #1 Bank 1 & 2 lean

[aburk1978]

Hello, new to the site. I just bought a 2001 EB 5.4 with 158K. I was driving it home from Indy the day I got it (as is of course), and it started running rough when I applied a bit more accelerator while cruising around 70 mph. Started reading about it on this forum and figured it was a bad COP. Next day it finally threw a code, so I took it to Advanced for a free scan and it came up P0301 Cyl #1 misfire; Bank 1 and bank 2 lean (forget code #'s on that) and something about battery voltage, although no problems starting or holding a charge or anything. So, today I was reading that you can check if the coil is bad by unplugging it while the engine is running. So, I did that on #1 and it ran much worse (was idling ok at the time). I thought I had read that if the coil was bad, it wouldn't make any difference when I unplugged it??? Also, I was having trouble unplugging the connector on top of the coil on #1, so I tried on #4 which was a little easier to get to, and the locking tab broke off so it just pushes back on now but wont "click" into place. Am I going to need to replace that plug and, if so, how big of a PITA is that gonna be? People on here have mentioed replacing coils, plugs, AND wires??? Are the wire on top of the coils what they are referring to, since there are no traditional "plug" wires???? I'm freaking out a little because I just bought this thing 2 days ago, and I'm not sure I want to touch this thing now. Any help would be GREATLY appreciated!!! Thanks in advance!!!

 

[bedrck46]

Somehow you have me confused You say #4 was easier than #1 to unplug?????

When sitting in the drivers seat the # 1 would be the plug/coil in the front of the engine on the Passenger side Then would be #2, 3 and 4 as you move to the firewall.

Plug/coil on the Drivers side would be #5, 6, 7 and 8 from the front of the engine towards the firewall.

Bank #1 is the side that has the #1 plug/coil on it (passenger side)

Bank #2 is the drives side

Kindly repost which wires you disconnected because normally #4 and also #8 are the hardest plugs/coils to get to

 

[bedrck46]

Would also suggest that you check on youtube for videos for HOW TO change plugs/coils on the Ford 5.4 engine

 

[BAD RONALD]

...took it to Advanced for a free scan and it came up P0301 Cyl #1 misfire; Bank 1 and bank 2 lean (forget code #'s on that) and something about battery voltage... the locking tab broke off so it just pushes back on now but wont "click" into place.

Do not freak out over breaking the connector tab. I think I have at least one that is busted off on my '01. You must, however, make sure the connector is and remains solidly plugged in.

A misfire has causes other than a bad COP. You need to dive into cylinder#1 to check conditions there. You could learn about the other cylinders depending upon what you find. Examine the COP boot and sparkplug. #1 is pretty easy to access.

Lemme guess on the lean codes...PO171 and PO174 sound familiar?

Low battery voltage can wreak havoc with these trucks. Check on the age of the battery.

 

[FordandPolaris]

I would say 90% of the time you can replace the COP and plug and the misfire will go away. Like bedrck46 said, I think you have the cylinders backwards.

 

[aburk1978]

Somehow you have me confused You say #4 was easier than #1 to unplug?????

When sitting in the drivers seat the # 1 would be the plug/coil in the front of the engine on the Passenger side Then would be #2, 3 and 4 as you move to the firewall.

Plug/coil on the Drivers side would be #5, 6, 7 and 8 from the front of the engine towards the firewall.

Bank #1 is the side that has the #1 plug/coil on it (passenger side)

Bank #2 is the drives side

Kindly repost which wires you disconnected because normally #4 and also #8 are the hardest plugs/coils to get to

Sorry, I meant #5. So, I unplugged #1 and #5.

 

[aburk1978]

Do not freak out over breaking the connector tab. I think I have at least one that is busted off on my '01. You must, however, make sure the connector is and remains solidly plugged in.

A misfire has causes other than a bad COP. You need to dive into cylinder#1 to check conditions there. You could learn about the other cylinders depending upon what you find. Examine the COP boot and sparkplug. #1 is pretty easy to access.

Lemme guess on the lean codes...PO171 and PO174 sound familiar?

Low battery voltage can wreak havoc with these trucks. Check on the age of the battery.

Yes' those are the codes. I also noticed the negative battery cable was a bit loose , so I cleaned and tightened both of them and it ran a bit better, but still rough. Hasn't thrown the codes again yet, but I'm sure it will. Battery is less than 2yrs old.

 

[aburk1978]

Bad Ronald....how would you suggest keeping the plug in place? Should I use silicone or something else to hold it?

 

[aburk1978]

I would say 90% of the time you can replace the COP and plug and the misfire will go away. Like bedrck46 said, I think you have the cylinders backwards.

I had 4 and 5 mixed up for some reason. I unplugged #1 with it running and it ran much worse. It was idling OK at the time. It is worse sometimes than others. I'm wondering if its the fuel pump or something. I should probably look at the plug itself first though.

 

[BAD RONALD]

You have a vacuum leak. The PCV elbow that connects to the back of the intake manifold is a common one. Do a search on it and look at a number of videos. You can fix this. Unfortunately for you it's a little trickier on the 5.4l than on the 4.6l- pay closer attention to video on the 5.4l but watch the 4.6l video anyway to get a better view of what you are trying to accomplish.

 

[BAD RONALD]

....how would you suggest keeping the plug in place?

Cable ties, electrician's tape or a combination of both.

 

[BAD RONALD]

Cable ties, electrician's tape or a combination of both.

Or if you wanted to spend more $$...

http://www.fordtechservice.dealerconnection.com/Renderers/ie/wiring/svg/images/connectorcatalog.pdf

 

[BAD RONALD]

Good misfire diagnostic information:

Part 2 -Coil-on-Plug (COP) Ignition Coil Misfire Tests (Ford 4.6L, 5.4L)

Your situation is well covered here. Note the other causes of misfire. One of them is a fuel problem. You have a known lean condition. Fix your vacuum leak (hope it is a simple one). Once that is taken care of look further into the cause the misfire in cylinder 1. I would inspect the COP and sparkplug as supported by the other posters on this thread. If you find a neglected COP(especially the rubber boot) and sparkplug, consider changing out all cylinders.

 

[aburk1978]

You have a vacuum leak. The PCV elbow that connects to the back of the intake manifold is a common one. Do a search on it and look at a number of videos. You can fix this. Unfortunately for you it's a little trickier on the 5.4l than on the 4.6l- pay closer attention to video on the 5.4l but watch the 4.6l video anyway to get a better view of what you are trying to accomplish.

Will a vacuum leak also throw bank 1 and 2 lean codes, in addition to a cylinder #1 misfire?

 

[aburk1978]

Or if you wanted to spend more $$...

http://www.fordtechservice.dealerconnection.com/Renderers/ie/wiring/svg/images/connectorcatalog.pdf

Electrical tape it is!!!

Just had a guy at work replace #1 coil only while I was on a run (drive a truck). Getting ready to leave work now, so we'll see how that goes. If it's still giving me fits, you think the pvc elbow would be the next route to go? If I find out the plugs need replaced, I may have someone else do it. I heard it's a nightmare if you bust one off.

 

[aburk1978]

Don't know if this could be related in any way, but it has also been doing some weird things on the last to mornings on the way to work. After I get about 5 miles or so down the highway, the heat will shut off briefly (I have automatic climate controls) and the screen on the climate controls will light up everything ( "888" + all other LCD indicators) and the ABS light on the cluster comes on. All of this happens for about 4 or 5 seconds and then the heats comes back on where I had it set and the ABS light goes out and all is normal again. Sounds like a case of electrical gremlins to me. Could it be the computer? What about the low voltage (although the voltmeter is in the middle or just a hair above the middle of the normal range so it seems fine and nothing else that I've notices, except maybe a slight alternator whine at low RPM's. Any thoughts???

 

[FordandPolaris]

Will a vacuum leak also throw bank 1 and 2 lean codes, in addition to a cylinder #1 misfire?

Vacuum leak would probably not cause the misfire, but it would cause a lean running condition.

 

[BAD RONALD]

If I find out the plugs need replaced, I may have someone else do it. I heard it's a nightmare if you bust one off.

You do not have to worry about breaking plugs off. This is a problem for 3 valve engines in 2005-2008 model years. That said, a plug change on your truck is NOT inexpensive.

You do need to ask yourself how much repair work you are prepared to take on. Do some searches on this and other Ford truck sites to learn about common Expedition problems and their costs. From there you can search videos on the repairs and see for yourself if they seem realistic for you to do. You will be surprised how many Expy videos you'll find. Some homework could end up saving you a ton of cash.

 

[aburk1978]

You do not have to worry about breaking plugs off. This is a problem for 3 valve engines in 2005-2008 model years. That said, a plug change on your truck is NOT inexpensive.

You do need to ask yourself how much repair work you are prepared to take on. Do some searches on this and other Ford truck sites to learn about common Expedition problems and their costs. From there you can search videos on the repairs and see for yourself if they seem realistic for you to do. You will be surprised how many Expy videos you'll find. Some homework could end up saving you a ton of cash.

I've done plugs on several vehicles, but they looked much simpler than this. I have watched a couple of YouTube videos and they make it look pretty easy. However, in a couple of the videos I watched, they mentioned the plugs breaking (I think he was doing a 2000 model year expy). In another video, the guy used a 3/8" impact wrench. I don't know how in the hell he found enough room to use it, but he did all 8 that way. He also said to do it while the engine is hot and they would come out easier and be less likely to break.

 

[aburk1978]

Well, replaced the #1 coil and no misfire so far Drove probably 40 miles or so and the SES light came back on (thought I might get out of the lean issue as well). So, I guess its the 90 elbow in the back to look at next. Could it also be an O2 sensor? What other vacuum lines besides the elbow at the back of the intake could it be? At least its not jumping and hesitating anymore! Making some progress I think! Thanks everyone!