I have an 86' 300zx and I am having fuel pump issues. The fuel pump doesn't turn on everytime I turn the key to the acc position. When I get it to work it only works for a second an then the car dies. Why wont the fuel pump keep pumping? I have replaced the old one thinking it was just a bad pump but the new one installed has the same problem. Odd thing is that when I had just two gallons left it ran fine and now that I filled the tank it wont keep running had to tow it home.

did you check the fuel pump relay?

There is no fuel relay that I can find under the Hood but I have checked the fuse under the dash.

Is there an obd or scan port in the engine bay? If so where is it located?