My Corsica used to run fine. Lately it starts up just fine but after a minute its like somebody turns a switch off and it immediately dies. It is a 3.1 Liter with fuel injection with about 138K miles on it. When I go to restart it the engine just turns over and sometimes it will start to catch but sometimes it wont. As the engine turns over, there is this heavy smell of raw gas and when it does finally start there is this huge plume of bluish smoke that smells of fuel that comes out of the exhaust. Sometimes when it starts it wants to shudder (like there is a leak letting in air) and the exhaust rattles. After it does start and runs for a minute everythings fine and there is no more problems until the next morning when the whole cycle starts again. Need a lil' help here.