wierd running probs with 92 gt

my 1992 probe gt probe is having some wierd running spasm after it was boosting then let off. it smokes (smells like coolant), and runs really shitty. it had an exhaust leak somewhere around the manifold, now it seems even louder. could it be b/c i had to make my own gasket for the surface between the manifold and the turbo?, and maybe the heat from the blown gasket blew against the plastic zip tie holding on the larger hose going to the turbo from the block. if you think it could be something else please let me know.