I own a Ford S-Max 1.8 Turbo Diesel 07 plate. Out of the blue the engine started to make a very unpleasant noise! And started having slight loss of power issues. It sounded like extremely loud tappets, and the sound got quicker when i revved the car. So i took it down to the mechanic that i use straight away. He took the head off, and thought that it was the pistons maybe hitting the valves, as some of the valves looked damaged. Sorry its brief, im not mechanically minded! So the head was sent away to be reset or whatever needs to be done, and some valves replaced. The mechanic got the head back, rebuilt it, and guess what, no change! He says now that it must be the bottom end of the engine, and it may be easier to replace the engine! Obviously thats going to be very, very expensive, and if anyone could give me some advice on the best thing to do next, it would be greatly appreciated. Many thanks in advance.