1999 Ford Mustang 3.8
It seems at low speed my car randomly decides to shut down some cylinders or feels that way. Car loses power you can push the pedal on the floor and get slow acceleration. I have changed the plugs, wires, coil pack. When you shut the car off and restart it all is fine for the first couple minutes or seconds depending. This has got me really confused hopefully someone can help. Also when this happens the car begins to idle really rough someone that was listening to the car when this happened I gunned the gas and they noticed that a soot type cloud came out the exhaust.