My car is running weird?

if its burning alot of oil your head gaskets probably blown. if its losing oil it could be a leak. there different so if your exhaust smokes alot thats a sign of a blown gasket. older pontiacs are known for having troubled transmissions so it may be your tranny is going out as well and your carburetor/ or o2 sensor may be going out if it is shutting off at stops. typically thats a cheap fix. you have not specified what hose you tightened and there are many hoses in the system but it is very likely your radiator if a hose fix didn't help it.