4.0L V6 #5 cylinder misfire

[NotAFordGuy]

We have been proud owners of an '03 Eddie Bauer Explorer. It's got a FlexFuel 4.0 V6, all wheel drive, automatic transmission, optional 3rd row seating, and ALL the gingerbread you could ask for.

It's currently starting and running. It has a constant SES light on that flashes at times. When the SES light flashes, it seems to run with all 6 cylinders. When the SES light is constant, it runs with a notable misfire and shifty transmission. There's new plugs and wires, but not a new coil pack. I found the #5 cylinder plug to be loose, so I tightened it in.

If I pull the negative battery cable and reset the computer, the powertrain runs like new until it "remembers" that it has a misfire and a shifty tranny. I may take this thing to the dealer tomorrow to get answers. If you can cut me off at the pass, any help would be appreciated. The 4.0L V6 has 184K+ on the clock. How many more miles are these engines capable of? Are we near the end of this vehicle? the rest of it is in great shape and we take good care of it.

When it's driven at a constant speed, the engine feels "missy", the tranny feels "slippery" and doesn't know what gear to be in. When I floor it, the miss goes away and the tranny shifts and performs like new. Any help is greatly appreciated and thanks in advance!

 

[mendy]

Pull the lead and plug out and check it for spark against the block.
Or just change the coil pack

 

[NotAFordGuy]

Thank you for the reply and the information. What's the life expectancy of the factory coil pack? Is that a pretty common part to fail on these engines?

 

[Tech By Trade]

Coils pretty solid. When the fuel filter clogs, or the pump gets weak it likes to starve 5. I would have a look at the pressure on the rails too.

 

[NotAFordGuy]

Replaced the coil pack and the overall performance got a little better but definitely didn't cure it 100%. I'm trying to change the fuel filter and cannot get quick connect ring to budge. I have a fuel line disconnector tool that I can get most of the way into the fitting, but not the lase 3/16" that I need to pop the fitting loose and disconnect the fuel filter. I've been at it for roughly six hours. What size of quick disconnect tool should it need? If anyone can help,please do. I'm at a loss and ready to set the thing on fire and walk away.

 

[mendy]

maybe get the fault code read

 

[kryhavoc]

heh... the old set it on fire and walk away. We all get that! I used a lisle deep plastic set of fuel line disconnects i got at advance and still had to use the swear word extensions to get mine loose. everybody hates it but look at it this way... you are doing it for the last time EVER!

 

[NotAFordGuy]

I got the fuel filter in, but what an awful job. I also replaced the #5 injector and am still experiencing some rough idle. There's also a strong smell of exhaust in the cabin while driving. Does anyone have any ideas?

 

[NotAFordGuy]

My cylinder #5 misfire turned out to be a broken plug wire. Go figure. I was getting spark, just not enough of it., and at the wrong times. I replaced the plug wires and it's running and shifting like new again. Thanks for the help, guys! And I mean that sincerely.