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while driving yesterday, car had total power loss.. cranking it thereafter resulted in flat battery.. so chucked in a new battery but cannot hear the usual fuel pump whine and prime in the boot.. have checked all fuses..

opened fuel pump cover with ign on, both fuel lines were easy to squeeze.. im assuming if it was being primed by the pump, one shud be hard and filled with fuel.. what else can i check.. any suggestions welcome..

btw does anyone have a spare gtr fuel pump i can buy/borrow.. and recommend a decent towing company in western syd

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you could pull the fuel line at the fuel rail while the car is off, hold it in to a bucket, then turn the key to start and see if fuel gets pumped out.

if it does, fuel pump is working and problem maybe in the injectors or ecu to tell the injectors to open/close etc.

But since you can't hear the pump prime, I'd suggest it's probably a problem there.

You could go old skool and have a mate crank the car over while you smack the fuel tank with a pipe to see if you can jolt the pump to start.

yeah figured the usual noisy priming points to the fuel pump.. tried smacking by hand the tank from the bottom and around the fuel pump cover hoping it wud do something..

the car did a power run for 1st time few days ago.. im thinking it might have sped up its impending death.. judging by the fuel pump cover, car still has stock pump..

maybe i was doing something wrong in the dark last, but couldnt get a reading from +ve wire on the 2pin connector with multimeter.. was thinking of supplying power directly to see if it primes.. otherwise issue maybe the power feed from battery??

Other thing to check, silly as it is, is the Cam Angle Sensor... if the plug comes losoe it will crank with no go.

Happened to me once, I felt like a tool.

umm good point.. on the day of power run.. i could see the mech doing things around there and fpr.. perhaps he didnt reconnect it properly..

update - fuel filter is clean, have injector pulse and spark. Can any1 help out with rb20 or 26 CAS near parra today??

call me on 0434284342

If the CAS was stuffed, then it wouldnt have started with the direct power feed would it?

BTW if you want to check to see if you're got the same problem as me, the fuel pump control modulator is behind the trim on the drivers side back seat. You need to take the drivers seat belt top mount off to get at it. I also have the back seat out ATM because i was tracing wires....

issue fixed.. fuel pump and relay earth both werent working.. created new earth new the fuel pump control module and one on the relay.. car started fine thereafter..

only issue now is fuel priming now doesnt stop after 5odd secs now.. just keeps going.. im thinking perhaps the pump relay needs replacing.. any thoughts, will it create problems down the line

only issue now is fuel priming now doesnt stop after 5odd secs now.. just keeps going.. im thinking perhaps the pump relay needs replacing.. any thoughts, will it create problems down the line

Looks like the FPCM also switches at least a soft earth, so maybe the extra earthing is stopping for module from working as well as it should;

From this link

"the factory ECU's on R32's trigger a soft earth for the f.pump; lower flow at idle,". Check the rest of the thread for more info. I certainly got mindf**ked trying to understand how it was all working, but i wasnt expecting earth switching.

umm yeah exactly. the + is always full voltage and they regulate the power via the earth. nissan actually do this with a few electrics (no idea why, 2 stage boost on a 33 gtst is the same). Anyway, the standard fuel computer in the drivers rear drops the earth at idle, you can bypass it by just earthing the fuel pump wire to the chasis. And if you still have problems run a + wire direct from the alternator or battery to a relay and then to the pump. There is a detailed thread on here somewhere on how to do it

fuel pump wiring is a common problem in 32s

umm yeah exactly. the + is always full voltage and they regulate the power via the earth. nissan actually do this with a few electrics (no idea why, 2 stage boost on a 33 gtst is the same). Anyway, the standard fuel computer in the drivers rear drops the earth at idle, you can bypass it by just earthing the fuel pump wire to the chasis. And if you still have problems run a + wire direct from the alternator or battery to a relay and then to the pump. There is a detailed thread on here somewhere on how to do it

fuel pump wiring is a common problem in 32s

interesting.. i have already earth'd the earth wire leading to FPCM so now im constantly delivered full voltage to the pump even when idling right?? will the life span of fuel pump decrease dramatically using it this way.. yet to open FPCM to check for broken solder.. can the relay itself be faulty?

interesting.. i have already earth'd the earth wire leading to FPCM so now im constantly delivered full voltage to the pump even when idling right??

Yeah i think so. The FPCM would switch the earth via a resistor at idle, to lower the voltage at the pump. Since you've made a direct earth it will bypass the resistor.

will the life span of fuel pump decrease dramatically using it this way..

I'm guessing the reduced voltage is to stop too much fuel circulating and therefore heating up - can anyone confirm?

yet to open FPCM to check for broken solder.. can the relay itself be faulty?

Yeah but the relay is easy to check. Run 12 volts through the solenoid pins (the pinout is usually stamped on the cover, from memory its the pair of contacts that are the furthest apart). You should hear it click. Check that the other two pins go from infinite to 0 ohms resistance when the relay is activated

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