Fuel Pump Question

[levizzle]

So my R32 GTR doesnt want to start anymore. It was working ok until it started dying randomly and would just lose power. Once it died and wouldnt start, so I thought it could be the afm's, and since I had some spare I tried swapping those in to fix the problem. The engine started and worked really good, which was good until I turned the car off and next time I tried to start it wouldnt start. It would never stay on for longer than 4 secs since then. So called the raa, he checked the wiring to the fuel pump while I turned the ignition. He said power would come for 4 secs before turning off. So my question is, is 4 secs normal for priming the pump and then its not powering anymore because the engine isnt running or should it continue longer? My next step is to power the pump directly and if that works ok, look for boost leaks.

[DVS JEZ]

4 seconds is normal but he should have checked it during cranking and when it ran for 4 seconds.

Does it blow any smoke when it starts then dies?

[levizzle]

Yeah thats what I meant, i was cranking the engine and he was measuring it. I couldnt see any smoke coming out of the exhaust. And it won't run at all now, its like there is no petrol coming.

Edited April 23, 2011 by levizzle

[DVS JEZ]

So it just primed then nothing more? Does this happen everytime?

Try powering the pump as u said and see what happens.

[R.3.2.G.T.R]

Could be faulty fpcm, u can earth it so fuel pump run full voltage all the time

[levizzle]

Well it happened everytime he was looking at it so yeah. He would count 1, 2, 3, 4 as I turned the ignition, did it about 3 times in a row. Where is the fpcm found exactly?

[R.3.2.G.T.R]

Well it happened everytime he was looking at it so yeah. He would count 1, 2, 3, 4 as I turned the ignition, did it about 3 times in a row. Where is the fpcm found exactly?

Drivers side bottom trim next to the rear seat

[levizzle]

Ok found it. Do I do anything with this box or should the fuel pump just be grounded to the chassis or this box grounded to the chassis? Also got a new question, I found a random purple wire going the length of the car and it goes into a plug in the kick panel. I took a pic can anyone recognise this plug?

[levizzle]

And another question, what is each plug on the fuel pump? The raa guy tested the brown plug, should have he been testing the grey one on the right? Anyway i havent had time to directly attach the fuel pump to power, but I am not sure the pump is the problem anymore. I got someone to crank the engine today while i listened closely to the pump and it was making a small humming sound which sounds like to me that the pump is fine. How do you test the wires with a multimeter? Next would prob be check that there is fuel pressure, but now I am starting to think maybe its no spark coming. SO then how do you test the spark is good? I have never had to test these things on a car before.

[The Dan]

Might sound silly but have you actually checked for fuel pressure/flow yet? or are you just taking wild stabs in the dark?

[levizzle]

I think I like to make wild stabs at first. So nah I havent checked flow yet but thats on my list of things to do. I have found another thread similar to my problem so I will copy the things suggested there.