Vs commodore fuel pump head scratcher

[sproulee]

Hi guys,

I have recently done an engine swap in my 95 vs executive. I wired everything up went to start it and all it did was crank. First thing I checked was spark. Second thing I checked was fuel. I noticed my fuel pump was not priming after letting it sit for about an hour before trying to start again, this time listening for the fuel pump. After I discovered the fuel pump wasn't working I immediately got the test light out. THIS is where it gets weird. Under the hood, I'm getting a great reading, test lights going nuts on everything to do with fuel pump. At the pump itself however the reading is THERE its just extremely faint. I changed the fuel pump anyway (thought it might have just been dodgy internals or something) but still have the same problem. After this i then proceeded to check all the wiring from the fuel pump to the relay under the bonnet and didn't find any problems with the wiring. Anyone have any suggestions on where to go from here or even better had this problem and fixed it?

Thanks in advance

 

[Bowen]

Earth? Second thing I would be checking is whether or not the ECM is letting you start it usually does this with fuel cuts but in saying that its providing spark? Which is strange, do you have a multimeter? I would be checking the earths make sure they're all okay, and maybe just check what current it's getting because it might use say a 9V current like injectors do? I'm not sure someone with a little more knowledge please help lol

 

[hako]

The strange reading you're getting is because you are measuring the fuel gauge current and not the pump current - you cannot measure this at the pump unless the engine is actually running.
From the sounds of it the immobiliser may still be on - does the red flashing light go out when you turn ignition on?...if not then it won't start.
I'd hot wire the fuel pump (violet wire at pump) and see if it runs.
Good Luck.

 

[Not_An_Abba_Fan]

Is the oil pressure sender hooked up? And is it good? If it is faulty, it cuts the power to the pump as the ECU thinks there is no oil pressure so it will not start.

Other than that, as above. It could be the contact ring on the ignition.