I originally brought my truck into a Ford dealer thinking it was a converter on the transmission. The ford mechanic test drove it with me and confirmed that was he problem. $240 later and it was still doing the same thing. I returned it and they then told me it was the number 6 spark plug and coil. They recommended I replace all the spark plugs for a cost of $650. I asked if they just replaced the #6 plug and coil would it fix the problem. They said yes but to eventually have the other plugs changed. This one plug and coil repair was another $229. So guess what, the truck is still doing the same thing. I have now spent $469 and it's not fixed. I've decided to replace the 7 plugs myself and I'm wondering what kind of job it is ? It's a 2006 Expedition 5.4L. Thanks in advance.....Rich

 

How can they charge you for not fixing the problem? Have a talk with the service manager. Take it right to the owner...walk right into the dealer principle's office if needed.

It was diagnosed wrong twice.

just be sure its not misfiring on the other cylinders. Did the repair work for a while or is this an intermitant problem?

 

They will tell me the other 7 spark plugs need to be changed like they recommended. What they fixed the 2nd time helped a little bit. At higher speed only. It is worse at 45 MPH. The tach drops from 2000 rpm to 1200 rpm and the transmission changes. When I press down on accelerator to gain speed it has something like a missfire until the tach goes back to 2000 rpm and the transmission goes into a lower gear. Hope I explained it well enough