Mariner 2+2 won’t stay running

Good morning everyone, I have been working on this issue for over a month and am finally stumped. I have a 1999 mercury mariner the 2+2 model. About a month ago I was out going about 3/4 throttle. When I came to a bridge I slowed down and the engine stalled. I couldn’t get it running again. When i got home I started to trouble shoot. I changed the fuel pump, all the lines, the ball. Still wouldn’t stay running. I saw there was some burnt lines in the stator so I changed the stator. Still was not running, after reading some of the forums I checked the spark and was only getting spark in cylinder 3. So I changed the trigger. Still not working. I checked all the ground and the trigger. Everything seems to be ok. Could anyone give any advice on why this won’t stay running. Please!