I have an 06 Eddie Bauer Expedition and am having problems with it starting. The engine will rev up maxing out the tachometer with a horrid sound and immediately drops the RPM's. I have taken it to North Central Ford in Richardson, TX 2 times now for the same problem and have been told that the computer has been replaced and the second time, the computer was re-programmed. Can you provide any assistance? The thing only has 16,000 miles.