My 1996 buick riv has trouble codes stating that i have a cyl 4 misfire. i figured blown head gasket, i just replaced the supercharge belt and took it out and my check engine light came on and started blinking, and the car chugges. Any info on possible problems or if you want more info plz contact me.

 

Not sure about the overhearing, yes, that could be a head gasket. But as for the other problem. For me all it took was to replace the coil pack.

 

Before replacing anything, why don't you consider switching spark plugs between the cyl next to #4 and #4. That way you might get away with just a plug replacement.

Compare the appearance of the plug from #4 cyl to any other plug. If compression is getting into the cooling system when the engine cools down it might just pull some coolant into the cyl and the white bubbled appearance of the plug could confirm a coolant leak.
There is a way to verify if combustion is getting into the cooling system. Some shops have a combustion tester to detect if compression is getting into the cooling system by measuring any air coming out at the radiator fill.