Di Turbo Fuel problems

[zookprojectfnq]

I have an 02 model 79 series with a 1hdt-fte. I am having fuel problems with the sub tank. The tank is full. the gauge also says its full. When I engage the sub tank and go for a drive, upon cornering on going up and down hill the fuel light comes on. Then as the gauge goes just below full, the fuel light mainly stays on. Then today it ran out of fuel to the fuel pump when I started it, after buying a pie at a servo. So I managed to get it to the bowser and the main tank was empty but the sub tank was full. I could only fit 5 ltrs in it. so I just filled the main tank and did that.

I was chasing fuel lines back from the tank and there was 2 change over switches. One for fuel to the pump one for fuel return from the pump.
All I can think of is that it might be changing the fuel return switch and not the feed line.

Where is the fuel light sensor from. The fuel tank or fuel filter

[zookprojectfnq]

Checked with test light and both switches are getting power when sub tank is turned off. both switches seem to be clicking

[Northside 4x4]

Blockage could be one issue, using compressed air is one way of checking if you are able to blow past the change over solenoids while it is switched on.

Sounds a bit weird that the fuel light is staying on though, this would indicate that either the float is stuck on full, or there is an electrical problem with the sender unit. I would be leaning towards the latter.

[zookprojectfnq]

Thanks mate I will try some compressed air but I know the sub tank is full as I can not get any more diesel in there

[Northside 4x4]

Let us know how you go
Always good to get a final result on these threads, as to many of them are left to go without a fix being posted up. Which is no good to future users