This may seem like an odd request for a preparedness site but hey, I am willing to give it a shot. My wife drives a 2007 Ford Expedition XLT. It is the 4×4 model. A few weeks ago the vehicle started running extremely rough. I know little about cars but I felt it was obvious it was not firing on all 8 cylinders. I had the check engine light check and it came back a couple cylinders were misfiring.
I suspected the spark plugs needed to be changed. I did a bit of research and discovered changing the spark plugs on this beast is a huge problem. The spark plugs are two piece models and due to a horrible design from Ford carbon builds up and locks the plugs into place. Performing a spark plug change often results in broken spark plugs. A local garage with a good reputation was contacted and I had them perform the spark plug change. Sure enough a couple broke and had to be extracted. Additionally one coil pack was replaced.
After all the work was done to the tune of close to $500 the truck ran very well with only a slightly rough idle. Two weeks it ran great and then started getting some hesitations. Between 40 and 50 mph there a definite hesitation and vibration that can be felt and heard. The hesitation is short lived as once I speed up to 50 it goes away. It seemed to get worse and worse and I could feel it misfiring periodically and the check engine light came on.
Another visit to the local AutoZone provided misfiring cylinders as the code. I decided to remove all the spark plugs and check them. They all looked good however I found one that was not tight in the well and I was able to unscrew it by hand. After checking all the plugs I ran the vehicle – no change.
A member of my preparedness group suggested I try resetting the vehicles computer. I disconnected the battery for about one hour. Upon reconnection and taking it for a test drive it seemed worse at first but then smoothed out. This step provided some success as it ran better but still has the hesitation and what seems like misfiring between 40 and 50 mph.
This is still how it is running. I can feel a “skip” every now and then while cruising however between 40-50 it is pronounced.
I have tried several Seafoam Gas Treatments and also tried the Seafoam engine treatment through a vacuum tube.
Again – I am far from being an auto mechanic but my next step is to change out all the coil packs. Oh – no check engine light anymore which I find odd as there is a problem.
The car is drivable it is just irritating and I would hate to have my wife be driving through downtown Charlotte, NC and have a spark plug explode out the hood into orbit.
Figured just maybe someone would have some advice.
So – any thoughts?