My truck is running terrible right now. It has 107,000 miles on it and I don't know where I should start in trying to fix it. I had one of the COP changed about 5,000 miles ago, but I forgot to ask the mechanic which one went bad. I know that whatever is happening it is firing on 8 cylinders part of the time. When my COP went out, it was totally gone so I know what it feels like for it to be running on 7 cylinders. Now the truck sometimes has a surging feeling and I can tell it is really down on power. It is worst right after it shifts into overdrive or when it is going uphill. I searched this website last night and found a bunch of possibilities of what the problem could be, but didn't find an exact case that matched my situation. One thing that I did notice was the possibility of it being the fuel filter. I did fill up with at the worst gas station in my town on Friday and the problem didn't start until Sunday on that same tank of fuel. I went out last night to change the fuel filter because I had an extra one and spent over an hour getting absolutely nothing accomplished. I bought one of the fuel line disconnect tools from Advanced Auto, but still couldn't get the thing unhooked. I have changed the fuel filter before with not so many problems, guess it probably didn't help that it was getting dark outside. So here are my questions:

What should be the first place I look to solve this problem?
Should I take it to AutoZone and get them to check the codes for me even though I have no CEL?
Has anyone found any tricks to getting the fuel filter lines to come off?
Should I get a COP and start rotating it around to try and find a bad one?
Should I have the plugs replaced (107,000 miles on the original ones)? (I will be taking it to a professional to get the plugs changed if this is needed because of all the problems our trucks have had with blown plugs.)

BTW, I am at college right now so I don't have my usual stock of tools with me so some repairs may have to wait until this weekend especially since I have 2 exams on Thursday. Thank you for any help you can give. I want my smooth running engine back.

 

Start with the plugs. Have them replaced.I went right back with the OEM motorcraft plugs. How can you go wrong with over 100,000 miles of use. Plug problems often show up under load in top gear.
Make sure your wrench for the plug replacement is aware and torques the plugs properly.
You can have codes stored with out a check engine light.
Try cleaning/lubricating the fuel filter connections with a little WD40 prior to removal.

Have fun and how bout posting pictures of your truck with as many lovely collegants as possible.

 

Thanks peppermrj!

I just got finished changing the fuel filter. All it took was a little WD-40 and the fuel lines slid right off. The only problem was the new filter didn't help the problem at all. I am going to get the plugs changed as soon as possible and if I have time tonight I might run by AutoZone and see if they can find any stored codes. I am thinking about changing the plugs myself so I don't have to leave my truck at a shop. How hard is it and is there anything special I need to know so I don't cause one of the plugs to blow out after I change it?

Now as far as the last part goes I wish I had thought to take pictures of my beach trip last summer. That would have been good to post up here, but I didn't take any and now my girlfriend might have a few things to say about having all of those girls in my truck again.

Thanks for the help and if anyone else has any ideas please let me know.

 

Just got back from AutoZone and the code reader said I had a misfire on cylinder 4 (still no CEL). If I remember correctly this is the one on the far back of the motor on the passenger side. I know from searching on here that the best things to use are the Motorcraft OEM plugs. Should the coils be Motorcraft OEM? They stock the plugs at AutoZone, but where can I get the coils quickly other than the dealership?

I don't know much about working on these vehicles, but I would say I am average as far as mechanical skill. I change my own oil can do simple maintenance like changing plugs on lawn mowers and other small engines, but I have very little experience on computer controlled V-8's with fuel injection. Should I attempt replacing the plug and the coil since it is so far back on the engine or should I let a professional take care of this?

If I do decide to take on this task by myself does anyone have any recommendations as far as tools I will need or hints that will make the installation go quicker? (I know I should by a torque wrench for this one) Anything else I should know to keep the plug from blowing out in the future or to keep this problem from coming back?

From reading on here I have heard mention of people putting something on the plugs when they put them in. I can't remember the name of the stuff, but is this necessary and what is this stuff?

 

Dielectric grease. Looks like Vaseline. It prevents the spark plug from welding itself to the plug wire (or COPS). Buy a small bottle for a buck or two and slather it on the tops of the plugs before re-installing the COPS.

 

dielectric grease is a wonderful thing....NEVER go plowing or snowmobiling without it...dielectric.."keeps the electric from dying"...zap!