Car is a 00' Honda Civic EX Automatic, engine was just swapped for the same OEM motor D16Y8, engine runs great, had to replace the IACV must had gotten damaged in shipping, but the problem is maybe 1 out of 5 times the car will just rumble and die when you let off the gas going like 40 - 50 mph like when you brake and start to slow down. After that you have to give it a little gas and it starts back up fine again... there are no CELS and other than that the engine sounds and drives perfect; Anyone have ideas of what I can check first?