bills

i just bought a 1990 240 sx, with the ka24e when i bought the car it had a bad head.. i got a new head and got it back together it wouldn't run, i cleaned the maf and checked the plugs... long story short i got new wires, plugs, cap,timing kit. got it to run but it has a misfire i had a buddy come over to help me with it messed with some wires and what not, i dont know what we did but we got it to run and idle fine, i let it sit for about a week then i put new oil and filter today and went to start it up now it wont run unless i give it gas and it seems like its got a bad misfire again.. done a lot of reading on here but dont know where to start..btw im new to 240s