I also too my 2005 F150 to Crain Ford Chenal for service when my "Check Engine Light" came on & my truck was running very "rough". My F150 only has 48,000 miles on it as of May 2012 and Crain Ford tells me that: 1) The electronic test will cost me $122.91. 2) I needed to change all 8 spark plugs for $376.59 and, if their ford trained service tech's were to break any of the spark plugs, I would have to pay an additional $50 per plug to have them removed. (Open checkbook to an additional $400.00.) 3) One Ignition Coil was bad and needed replaced for $129.77. 4) Air filter was really dirty and needed replaced for $31.20. Their total service estimate was potentially going to be $1,190.24 with their highly trained tech's getting to my spark plugs.
I am retired and on a fixed income and could not afford this kind of service work. Although I used to do all of my own automotive service work, I haven't done so in quite a few years. I told the head service guy to install the Coil if it was bad and give me my truck back.
Within a mile of leaving Crain Ford my check engine light came back on and my truck continued running rough. Somehow I was not surprised.
I bought a filter at Walmart fot $10.00 and installed it in less than 2 minutes. I bought 8 sparkplugs for $100.00 and installed them myself & did not break any. The check engine light remained on and the engine continued to run rough.
I asked the counter clerk at an auto parts store if he had any suggestions and he told me that he actually had a machine to hook up to my truck that would tell me the code that was making my check engine light to remain on. I did not know this. He hooked his electronic machine up to my 2005 F150 and after a few minutes told me I had an oxygen sensor that was bad. He sold me the Oxygen sensor for $50.00 and showed me in a diagram where it was located. I installed in about a half an hour. Problem solved.
The wires on oxygen sensor that I removed had very obviously been cut. I am not sure why anyone would do that. With the location of this sensor and the difficulty of getting to the location of this sensor it would be a million to one for an object from the road to sever these wires in this particular manner.
In any case Crain Ford did not mention anything about an oxygen sensor being bad & the my F150 was running rough as soon as it warmed up after leaving their shop (that is the reaction from a failed oxygen sensor).
If it looks like a Ripoff and smells like a Ripoff and feels like a Ripoff, guess what - I would not take a gocart to this dealer to put air in the tires.