ok im 19 and dont no much about cars but my friend does and a guy a town over about 15 miles sold me a 89 cutlass supreme i went to his house and he said its been sittin there for about 8 months it ran when he parked it...well it didnt have a battery so i got one put it on and tried it and nothin so we tried jumpin it off and it just turned so i went and bought 4 gallons of gas and a bottle of Starting Fluid we went back and i filled it up and he sprayed the stuff in the carb and i turned the key and it would fire but only run when he was spraying it....he said it was knocking bad 2....so what should i do??? im pretty much stuck with payin for the car already so not gettin it is outta the ?...my friend said he bets its the fuel pump im gona tow the car here tommorow so if you can help me please do!