2000 Expedition runs rough and misfires
 

I just changed plugs in my Exp because of bad missfires in cyl 2/3. truck ran real good for about ten miles with no srvc eng light. after 10 miles light came on but truck still ran good. next morning it began sputtering when going up a hill but not as bad as before. the plugs I used were Bosch Plat 2. what could be the problem and are these plugs too hot or cold?

Has it thrown any more codes? Could be a lot of things at this point. Any codes would help to narrow it down. When you replaced the plugs, did you inspect the COP and boots carefully? I have experience with the boots cracking and grounding out. Throws a misfire code, and lots of folks have replaced the COP instead of the $4 boot.

missfire on cyl #3
 

I ended up replacing all the plugs and then replacing the COP for cyl #3. The truck doesn't run nearly as rough now but the srvc engine light won't go out. Not sure if this is still and issue or if the computer needs reset. What do you think. The actual codes were initially for missfires in cyl 2 and 3 before the plug change, after the plugs it was just for #3 and it has not reset since then.

PS the boots on all plugs were good, no cracking.

My 97 expy was missing during acceleration ...changed the plugs to bosch platinum...ran good for about 20 miles and then started missing again...went back to standard autolite plugs....hasn't missed a lick since...for some reason it hated those bosch plugs....go figure.

I have seen other posts about the Bosch plugs causing issues, but never personally experienced it. Unless the Bosch plugs are a totally different heat range, I can't understand the logic why they would not be compatible.

Yes, you should reset the PCM to clear stored codes. Drive for awhile and see if the Check Engine light comes back on and/or hook up your OBD2 tool to show any DTC's.

Autolite or Motorcraft copper plugs are the only way to go. Put a set of the Bosh +4 got a block away and ran like $%$# till I put good ole Motorcraft plugs back in.

I used the Motorcraft platinums that came with the truck. Never a days worth of problems in almost 140K miles.

I just bought a used 2000 Eddie Bauer Expedition. I am experiencing some rough running and sputtering too. I was thinking that it seemed like a fuel flow issue, but after reading these posts I am starting to think it might be something else. I have no idea where to look for codes though.... Any ideas?

If you don't have maintenance records I'd change all the filters and oil to start a baseline. What's the mileage on your 2000 EB? Look at the recommended maintenance and make sure you do it. If you have codes your engine service light (yellow engine) will be on. I've been using Motorcraft parts for most things on the engine (e.g., belts, plugs). I use synthetic oil so I don't use a Motorcraft filter, but I use to when I was using Mobile 1. Walmart sells them. The fuel filter in just in front of the gas tank, and you'll need a special tool to remove the fuel lines. I got mine (aluminum) at NAPA, but others may carry it. It is a scissor-like tool that closes on either side of the fuel line connector. You can try some injector cleaner, but I would recommend either BG or Redline because they are supposedly petroleum-based cleaners.
http://www.bgprod.com/home.html
http://www.redlineoil.com/
I would do everything else first before using any injector cleaner, because the gas you buy has cleaner in it too.

Thanks 2000Expy! I just bought the EB and when I got it home it was running a little rough. No engine light on. It has 125000 miles on it and i am not sure about it's prior owners maintence schedule. So I am sure it is do for a tuneup all the way around. It is an intermitant rough running though. And when it gets a little rough I can pretty much accelerate out of it. And when it is running rough it seems to affect the shifting of the transmission. Would any of this information change your recommendation? Thanks for the help!

Changed the fuel filter this afternoon, seems to have been the culprit.The EB is running like a top. I am still going to do a complete tune up. And now for a really stupid question....where is the PCV valve located on a 2000 Exp. EB with a 5.4 liter Triton V8?

Passenger side valve cover, right in the middle.

Watch those torque specs on the spark plugs! You need a wrench with Inch lbs and antisieze compound!

update 2000 expy misfires
 

I ended up changing out the COP unit for plug 3 and now the truck runs real smooth with no engine lights. I do have a noise from the front end that sounds like the Auto 4 wd kicking in when going up steep hills on pavement. It doesnt pull or anything like the 4 wheel kicking in just a noise. Any ideas?