I have 2000 mustang,stick sift.Recently it will while I'm driving and only when I start to slow down it'll just shut-off! It will turn back on when I turn the key and run fine,it does this AT least twice a day.I had it hook-up to the machine and no reading for it. Any possible ideas on what it could be??

 

you are stalling it.

 

Sounds like your losing power to the coil packs

 

I do know that it has a lil exhaust leak there is a custom exhaust that was put on the car.It only has 40,000 miles on it and this only starting happing within the last month.

 

Your TB COULD be getting stuck also. Try some carb cleaner in there. I had a 2000 Jeep Grand Cherokee that was doing the exact same thing. When I took it into the dealership, they said they couldn't find anything wrong with it, but they did clean out the TB. Ran like a champ after that. Too bad it took me $180 to figure it out.