I have a 2003 V6 mustang and the problem with the car is killing me since the engine light is not on and Ford dealer could not find what the problem was. All the readings are excellent. The engine gets too hot that almost impossible to touch anywhere near the engine, but does not overheat and the gages are all normal. There is a loss of power at times but not always. It seems to be running perfect night time, but during the day when the wheather is hot, loss of power is obvious. The car also starts jerking and idle not stable when waiting at the red light or something, but it does it for 2-3 seconds every minute or so and goes back to normal. When the car is in Park mode, it does not do it, only in Drive mode while I am pressing the brake at the same time. I changed the spark plugs, and wires, fuel filter, air filter, oil filter, battery. None of these worked. It feels like something is clogged up, I don't know...The engine runs very smooth and there are no leaks, smoke, smell or anything. This is driving me crazy, please help!!!