Need Help..I own a 1995 GMC Yukon GT. It has a new jegs crate motor plain Jane and a rebuilt transmission 4L60E. I can drive my truck and every now and then when I slow down close to stopping the truck will cut off. I can usually start it back up go on about my way. The map sensor I am using came off the old engine could that be the issue? Any ideas would be appreciated. I could also answer any questions if I didn't provide many details.