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V35 250Gt Fuel Pump Issue

beercat
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beercat Apprentice

beercat

Posted
Posted

Hi guys, I've been trying to figure out what's happening with my 2002 250GT and so far this is what I've been able to find using the NDS2 software.

Fuel pressure reads about 6.8 - 7.0 at idle to 10.3 at WOT. When I disable the fuel pump, let the pressure drop then enable it again, there's a whirring noise like a stuck bearing as the pressure builds up.

I'm assuming this is the high pressure fuel pump, although it isn't really specified (there's only 1 'Fuel Pump').

Has anyone else experienced this before? And if it is my high pressure pump, any idea what the issue may be?

Cheers

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https://www.sau.com.au/forums/topic/423822-v35-250gt-fuel-pump-issue/
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  • 1 year later...
Monzie Rookie

Monzie

Posted
Posted (edited)

Hi guys

I have a 2002 250GT V35 skyline, last week i took it for diagnostic cause the CEL came on and the results were as follows:

1. PO191 Fuel Rail Pressure Sensor Range/Performance

2. Mass or Volume Air flow Circuit

3. Knock sensor 1 Circuit High Input (Bank 1)

When i drove the car back home, there was no power in it at all, it would only get up to about 20 or 30kms/hr.

I changed the Airflow sensor and she seems to run a little better but there is no power in it, when i reach around 3000rpms she starts jerking.

Can anyone help me please. Do i need to change the Fuel Rail Pressure sensor? if so Where can i get one and does anyone know the Part number?

Please help. my email address is [email protected].

Thanks

Monzie

Edited by Monzie
scotty nm35 Grand Master

scotty nm35

Posted
Posted

The AFM is a common issue, especially in the turbo VQ25, but it sounds like you may be having issues with fuel supply.

I would start by checking the fuel pressure is within specs. Those high pressure mechanical pumps can fail, so can the one in the tank. Replace the filter intank for a start.

  • 3 weeks later...
Monzie Rookie

Monzie

Posted
Posted

Hi guys

So since the last time i posted a thread, these are the developments:

I changed the fuel rail pressure sensor. (what a mission to get to), the engine check light went off, drove it and it seemed a little better but still no kick down when you accelerate. it will drive normally, changing through the gears seems normal but when you put your foot down it just doesnt go like it should. the mechanic checked

the Fuel pump and filter in the tank and found the filter to be blocked, he changed both the filter and the pump in the tank with new ones and its still doing the same thing, drives normally and changes the gears normally but when you put your foot down there is no kickdown at all. now the diagnostic is reading the knock sensor as faulty, changed that as well and still no joy.

Can anyone help please.?

Monzie

scotty nm35 Grand Master

scotty nm35

Posted
Posted

What diagnostic reader is he using? Sounds like it's in limp mode still.

If there was a fuel supply issue, then the knock sensor would be picking up knock and doing it's job correctly. Not all faults will display an engine code, and sometimes the code it does show isn't related to the fault, but is a symptom of it.

  • 2 weeks later...
Monzie Rookie

Monzie

Posted
Posted

Hi Paul and scotty

Thanks for the responses.

Im not sure what reader they using but i think its the same one that our nissan dealer is using at their workshops.

The mechanic has removed all the catalytic converters from the vehicle ( not a problem in our country), we changed the fuel filter and pump in the tank as well as the sensors. took off the high pressure fuel pump that sits near the fuel rail pressure sensor (it was full of dirt) blew it out and tried it again but still doing the same thing, it drives fine but no kick down when you put your foot flat. the mechanic is suspecting that the high pressure fuel pump is gone, we couldn't strip the one we took off to really clean it out.

The mechanic said his getting another one off another skyline to try and see if there is any difference. he also told me that he has another skyline doing the same thing.

I really dont know what to do or think... they are such beautifull cars....

any suggestions????

  • 3 weeks later...
Monzie Rookie

Monzie

Posted
Posted (edited)

Hi Scott

Yes it was the HP pump, apparently there are some piston like parts in the HP pump that were not working to well due to sludge, he managed to clean them out and the machine started working again, its not 100% like before but still got loads of power, having removed the catalytics seems to have given it better fuel consumption.

the mechanic says it will be fine for now until i can buy a new HP pump.

he recommends that regular oil changes should keep it from happening again.

Thanks for all the help guys, and hope this will help anyone who experiences this problem in the future.

Edited by Monzie

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