Why wont it work?

[neiloakley]

I droped the two litre 8v in my nova today. It came straight out my other nova. However, the bitch wont start. When i switch the ignition on the fuel pump dont spin but if i just give it a +ve and -ve it does, and by doing this i got the engine started. Does it mean the fuel pump relay is fcuked?
Also, will the engine run if the ecu is fcuked? I.ve checked all the usual things like earths, fuel blah blah blah

[brian]

was the engine runin just before ya took it out?
if ya then what way is the relay wired? one wire from relay direct to pump and pump earthed? :?

[neiloakley]

everything was working fine before. The relay plugs into a socket coming out of the loom. The relay has more than one thing inside it. Should the fuel pump run with the ignition on but the engine off?
Thats what i want to know

[Dicko]

it wont run like that, the engine needs to be running!! the ecu tells the fuel pump to operate, and the engine will only run if the ecu is working as it also controls the spark+injection

[neiloakley]

catch 22. How does the engine start, if the pump does not start till after the engine is running? i.e how does the engine get the fuel it needs to start? I know there will be some left in there but eventually the system will depressurise. Can someone check to see if there fuel pump comes on as soon as the ignition comes on? Ta

[Dicko]

there is already some in the fuel rail, and when the engine is turning over it sends a signal to the ecu to produce a spark and to power the injectors and fuel pump

[neiloakley]

cheers guys. Got it working in the end. The live from the ignition to the coil was fucked. Had to run a new wire. Cheers anyways