OK so I have a 99 Eddie Bauer Expedition and its throwing like seven different codes. Misfires in 1,2 and 6 cylinders also shows it as being lean and possible EGR fault. I cleaned the EGR valve.This all started when it shot a plug out. Now I have cleared the codes and replaced the spark plugs and put in a helicoil in the bad cylinder, I also put in new coil packs on the misfire cylinders. But the truck still runs like a friggin turd nugget. What could I do next besides taking it to one of these local mechanics and recieve a royal *** reaming. Thanks in advance for all your thoughts.

 

Check all of the wired connections at the coils and injectors, also the vacuum lines and the inside of the elbows. You should also check or reverse the 2 EGR hoses from the left exhaust manifold to the EGR sensor on the intake manifold.

 

My first though is to take a video of you and the mechanic so that you can at least profit from such an act.

Secondly, after you cleared the codes have any come back? If so, what are they?

 

My 99 started running a little rough, killing at stop lights, low idle etc. Found I had lost the oil cap causing one side to run lean. No error codes this time but it has happened before and I got a lean bank 0 error.

 

I have cleared the codes and they have returned again and again and again. The guy at Autozone said that it shouldnt be even running right now. I have checked all the connections and nothing is loose. The misfire codes keep changing tho very odd. Started as 2,6 then 1,6 and now 1,6,7. I am changing the EGR today maybe it will fix it.
PS Could Ford make it any harder to change the spark plugs on the passenger side.

 

It would help me if you would indicated which engine you have in this '99. One engine this year uses coil packs and one uses COPs. (Or do all EB this year only have the 5.4? )

A misfires allows unused fuel AND oxygen into the exhaust stream. The HO2S doesn't see the unburnt fuel, but because it is an Oxygen sensor, it reports the excess oxygen to the PCM. The PCM responds by increassing the injector duty cycle to compensate for what it believes is a "lean" condiction. (Since there is only one HO2S per bank, the PCM doesn't know which cylinder is "lean" so it increase the injector on time for all injectors on the bank that is reporting "lean". Since you are having misfires on each bank, both banks are getting fattened up, ergo, your description that it runs like a "turd nugget".

Start with the first code set, as it is likely it can cause more than one code to be set. After that code is cured, then see if any other codes are re-set. If there are, work on the first code first and repeat.

We are probably having a terminology issue here. In Ford speak, a coil pack fires multiple plugs. (There are two coil packs on V-8s that use coil packs. If the systems uses a coil per each cylinder, they are known as COPs (Coil-on-Plug).

If your engine uses coil packs, you can switch them from bank to bank and see if the misfire follows the coil (or plug wire). If your engine uses COPS, you can swap the coil with a cylinder that is not reporting misfires and swap the plug boot with another cylinder and see if the misfire follows the coil or the boot.

Next try swaping the sparkplug of a misfiring cylinder with a good cylinder to see if the misfire follows the sparkplug - it's possible one of your new plugs is marginal. Hopefully you used Motocraft plugs?
If all else fails, try swapping the injector from a misfiring cylinder with one that is not misfiring and see if the problem follows.

May even have to do a compression check to be sure there is no mechanical problem. Is the helicoil cylinder one of the ones that is misfiring?

Good luck - hope you zero in on the problem---------

 

It has COPs sorry. I have checked all the plugs and they are fine and the cops are good too. I changed the EGR and the egr switching unit today. After I replaced it the expy ran better but still shuddering.

 

Oh and it is the 5.4 I have had no problems with this truck stall until it spit the plug out. Now the misfires keep changing cylinders. I have heard it could be the mass air sensor causing this too. I cleaned it and put in a new air filter.

 

How do you check the plug and COP? With an oscilloscope?

Did you try trading plug/COP of a misfiring cylinders with a cylinder that appear to be firing okay and see if the problem moves?

Is the helicoil cylinder one of the ones that is misfiring?

 

I have swapped them and checked them. Also pulled them out and checked to see if they were firing. All are good to go.

The heli-coil is one of the ones throwing a code, sometimes. Like I have already stated it keeps jumping cylinder misfires. It can show 1 and 6 now but after clearing codes says its 3 and 7. Completely baffling.

I am so done with this thing its unreal.

I am taking it out of town to my buddy's friend he is the lead mechanic and shop manger for a ford dealership. He says he can check it for about $45 and then whatever it is he can replace at his cost and labor. He has worked on my other cars and always done extremely well with them. Just hard to get time for him to work on stuff (very busy guy).

 

You may have fouled plugs.

 

This has already been covered.

 

Well, be sure and let us know what the solution was.

And could you post the specific codes that are coming up?

 

Please update this thread when you can, I've been having nearly the exact same issues and would love to know what you've found out.

 

don't know if you solved it yet but i had an explorer that had a random jumping misfire. i was stumped but finally found that the weight in the harmonic balancer broke and was spining free and throwing off the balance to fire the plugs right. basicaly retarding the engine to much. just a thought.