Fuel gauge issue

[fierce Lurker Find all posts View Profile Close fierce]

Okay I’ve seen people have fuel gauge issues but none with the same issues I have.

firstly it a 2011 150 GXL petrol with 145000km and yes it’s due for a service 5000km

the issue:
Driving along with a tad over 1/2 tank on the gauge and 380km left on the cruising range. Got 5km down the road and the cruising range zeros out the fuel gauge drops so far past empty I swear it’s off the clock and fuel warning light comes on.

i put 90lts in at the servo and start the car up gauge goes to dead on the empty notch and cruising range rises to lofty heights of 75km

travel for about 25km and the gauge shoots to Full and cruising range of 900kms



Thought nothing of it for about a week of Day to Day driving, then notice the gauge is about 1/4 left and 190km, Then again barely 10km later zero across all gauges. Another 75lts in to register empty and 75km cruising range.

Any ideas anyone, it’s driving me crazy as I don’t want to go anywhere in fear of running out of fuel.

[JimmyC Advanced Member Find all posts View Profile Close JimmyC]

I'd put money on a faulty sender unit.
The 150 series has an interesting fuel setup where the fuel pipe has a Y junction that splits the fuel being put in between the rear and the front tank. So (for arguments sake) if you put in 90L then 45 will go to the rear tank and 45 will go to the front.
Then when you run the car the fuel only gets sent to the engine from the front tank.
The rear tank (through Harry Potter magic) will fill the front tank until it is full. Then it will only be able to transfer fuel from the rear tank to the front tank to keep the front tank full while the engine consumes fuel from the front tank only.
Only when the rear tank is empty will the front tank start to empty.
My guess is that the front tank sender is either faulty or getting caught on something.

[Rossberg Lurker Find all posts View Profile Close Rossberg]

Mine has done the same thing did the sender unit fix the problem?