I have recently replaced my fuel injectors and the fuel rail on my 77 280Z. The original fuel rail was a one piece but I replaced it with a two piece fuel rail. After replacing the fuel rail I was left with two fuel lines with no attachment. Two of my fuel lines had no where to be attached. I was told to plug the two lines and I did.The car did start but it later began to miss and idle to high in first and second gear. It also later began to have trouble as if the plugs were bad. I had trouble starting the car and then replaced the plugs a second time and the car started right up.The car ran for a while and then started to repeat the same actions.My question is this do I have to replace the fuel rail with a one piece or is the fuel rail just hooked totally wrong. the fuel injectors are new, all the filters are new, the fuel line is all new fuel hose,and I've replaced almost everything dealing with ignition and fuel. I'm thinking that there is too much pressure in the fuel rail.If anyone knows if the spark plugs can be fouled out by too much pressure or flow of gas please let me know. Please send any suggestions.