Blown computer/Fried coils
I suddenly got a bad miss at 63k miles, for no apparent reason. The car is an '06 3.0 Fusion SEL. I initially got DTC P0302 -- #2 misfire. I pulled the manifold myself, replaced #2 coil and did all 6 plugs. Ten minutes after firing it back up the miss came back, with DTCs P0351, P0352, P0354 -- various misfires. I figured it was out of warranty and turned it over to a reasonably competent local who misdiagnosed it as a combo of 2 more bad coils and a bad injector. One of the coils was literally melted -- blistered, split plastic body, burnt smell, etc. While my guy was planning more trial and error on my dime, I found Ford TSB 11-8-2 -- entitled something to the effect of "MIL lamp with DTC P035X on 3.0/3.5 engines built before 1/1/08." The TSB diagnoses DTCs P0351, P0352, P0353, P0354, P0355, and/or P0356, when combined with visibly fried coils, as a blown PCM. The repair is to replace the PCM and coils, with a hint of SOME warranty coverage. I yanked the car and hit the local dealer. On seeing one of the fried coils, the dealer's tech, to his great credit, instantly recognized the problem, and the service guy, to his credit, determined that there was coverage for the computer itself, under the Federal 8 year/80,000 mile emission warranty. Up to 8/80, that covers "specified major emission control components," which is further defined to include catalytic converters; the electronic emissions control unit or computer (ECU); and the onboard emissions diagnostic device or computer (OBD) (if that is somehow different). I ended up paying top dollar for 3 coils and labor for the coils, but the computer, installation and reprogramming were all covered, which the service guy said would have run another $1400. It was nice to have coverage for it, since the factory warranty on 06's was only 3/36. I was also happy to find the dealer's guys right on top of the problem, even if the uncovered portion cost me top dollar. I can only imagine where I was headed with my local guy on a problem like this. TSB 11-08-02 applies to basically all 06-08 3.0 and 3.5 cars -- Fusion, Taurus, Edge, Zephyr, MKZ, MKX, Milan and Sable. I found a pdf of the TSB over at the Edge forum on a Google search. Had to register on the Edge forum to download it.