I went to leave my house today and my truck started acting crazy. It had a very rough idle and was vibrating badly. When I pulled out on the highway, it accelerated slowly and the check engine light started flashes on and off. I turned around and came back home. Anyone have any ideas. I am about to sell my truck and I don't want anything serious to happen to it. It seems like it is about to die whenever it is at idle.

 

year,engine,miles would be a good start

 

Sounds like a bad O2 sensor.

 

My truck is a 99 ORP with the 5.4 and 70,000

 

What's the state of tune or in other words what kind of maintence have you done. To me it sounds like you have bad plugs or a coil pack gone bad or both. Usually the flashing MIL indicates a misfire condition.

 

My guess would be misfire too. Wouldn't be surprised if it's good ol' #4 COP that's bad. Heater hose above can leak on it and kill the coil. Happened to my 97. Since you have the CEL, it'll know the "true story". Gotta get the code pulled to be sure.

 

I got the code run and it showed up as a misfire in the #4 cylinder. Should I even bother with changing the plug and wire or just mess with the coil pack. How much does a new coil pack cost anyway.

 

If you already have to change the coil pack just change the plugs, It's a bi+ch but if you have not ever changed them then go ahead.
make sure all the heater core lines are not leaking, and the condensation from the evap. line is not drippin on ur coil pack.

Go with motorcraft plugs, and be sure to buy ur coil pack from ford, 12 month warranty on their parts, however I have got 136k out of a couple of mine.....The coil pack cost's me around 54$, I get my stuff for list, I think it retails for 70-80, something like that, and if you change ur plugs put some dielectric grease around the part of the soil boot that sits at the top of the plug cylinder. It helps to keep water, coolant and dirt out.
If you change them yourself be sure to blow out the plug holes with lots of compressed air. Dirt and grime will collect in there, and when you take ur plug out and try to put the new one in you will drop the trash into the bock and also booger up your aluminum threads, that is not a good thing.. Hope I didnt bore u.LOL


5.4

 

If you were looking at the motor, where would the #4 coill be?

 

Passenger side, all the way in the back..........

 

Good ole' number 4........

 

Since you're selling the truck, just change the coil. You may want to add a new hose clamp to the heater hose, though.

 

#4 Cylinder Bit me in the @$$ too! I still got the scars on the arm to prove it! What a pain. Boy what fun!


Scott

 

Just wanted to say thanks to everyone for their help. I will post again later today to tell how the coil change went.

 

Well, I changed out the coil pack and put in a new motocraft one. The truck still ran lack crap. My dual exhaust was sounding off at a very bad idle. The truck has a lot of hesitation and has no power. I didn't change the plug, but should I go back in there and do it. However, the check engine light didn't come back on when I took off on the road. Please help.