[Wingo]

Took my 2005 f150 to the shop with a check engine light. Had an extended warranty with $100 deductible, so I took it in. Bad #8 coil and they wanted to change the plug. With 82K on the other plugs I wanted to change the rest. They broke three off including the #8 cylinder that had the miss. I got the truck back and noticed a high rpm rattle. Check engine light came back on. After a week of codes going active and inactive they determined the exhaust valve was sticking on the #8 cylinder causing a rich condition on that bank of cylinders. Removed cab and head, rebuilt valves and returned truck. When I picked it up it had a rough idle when cold. Check engine light came back on, cylinder misfire #8. They put new valve springs and replaced cats with no results. They then said they didn't know what was wrong and needed a Ford engineer. The engineer told them to remove the head again, so off with the cab for the second time. Here I sit two truck payments later waiting on the engineer to make a call.
My costs $752, warranty paided $3200, looks like the dealership is working with Ford for the last valve springs, cats, and latest teardown. Expensive plug job!!!