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Fuel Gauge Problem?

YangLIU
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YangLIU Rising Star

YangLIU

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Posted (edited)

Hello,

my car could run 330-350kms and 1/4 tank left on fuel gauge, and it needs about 45L to fill full. so it is about 13L/100km, it seems ok.

I know NM35 feul tank is 80L. my question is why i used 45L but the fuel gauge shows only 1/4 tank left? is there any problem with it?

btw, i never try to drive until empty light on. maybe i need to run once until empty light on?

Edited by YangLIU
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scotty nm35 Grand Master

scotty nm35

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Posted

Depends on a few things. The fuel level sensors that reside in each side of the tank could need a clean, they build up a varnish from the fuel.

The fuel sometimes sloshes over to the other side of the tank, and the computer that works out the level from the twin sensors is a little stupid I think. Eventually the two sides level out and the gauge should read higher again.

YangLIU Rising Star

YangLIU

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Posted (edited)

Depends on a few things. The fuel level sensors that reside in each side of the tank could need a clean, they build up a varnish from the fuel.

The fuel sometimes sloshes over to the other side of the tank, and the computer that works out the level from the twin sensors is a little stupid I think. Eventually the two sides level out and the gauge should read higher again.

most time when i park the car for long time then start it, i found the fuel gauge is obviously then last time before turn off engine.

maybe i need to clean fuel level sensor?

btw, could you advise which type of fuel filter and fuel pump are suitable for NM35? it is a good chance for changing the fuel filter/pump with cleaning fuel level sensors together.

Edited by YangLIU
scotty nm35 Grand Master

scotty nm35

Posted
Posted

Any aftermarket pump will require the wiring be upgraded. I have 255's in stock if you need one for $110.

The filter and 2 x Oring part numbers will be in the M35 parts thread.

Clean the carbon on the sensors with contact cleaner, ethanol or metho.

YangLIU Rising Star

YangLIU

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  • Author
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Any aftermarket pump will require the wiring be upgraded. I have 255's in stock if you need one for $110.

The filter and 2 x Oring part numbers will be in the M35 parts thread.

Clean the carbon on the sensors with contact cleaner, ethanol or metho.

cool! i will arrange that when next service. also will contact you to buy the pump. thanks mate.

Hertz Donut Proficient

Hertz Donut

Posted
Posted

No idea, I haven't had the enthusiasm to check it more closely, could be a dirty sensor as mentioned. The car's been acting as a tool shed for the past few weeks so I've only just got it moving again (and took it for a 300km trip to celebrate). All I know is it operates as expected above 1/4 tank, then once it drops below 1/4 sometimes it'll bounce back up to just below 1/2. Shut it down and restart and it's back to normal.

  • 10 months later...
privatepang Apprentice

privatepang

Posted
Posted (edited)

Sorry to resurrect this thread. So just bought my M35 VQ35 Stagea recently and wanted thoughts as to whether the sender is the issue or the gauge.

Bought car and at the time, fuel gauage read 1/2 tank and didn't move much from 1/2 tank after about 100kms of driving

Parked the car for couple of hours, came back and car was hard to start but i didn't think much of it when it did start.

Car then reads 1/4 tank. Drove for about 6kms and car died. Ran to the closest servo and filled up with 5L jerry can, car now reads 1/2 tank again and looking at the estimate kms to empty it reads 188kms!!

Filled it up again at servo and filled up another 73litres and car now is reading full...

Hard to work it out I guess but thoughts?

Edited by privatepang

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