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Vz sender problem

hobbsy4

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05 VZ Calais 5.7L Sedan
Gday All,

Seems to be a problem with my sender unit in the tank, at 1/4 fuel level or lower I'm starved of fuel. It happens when the car is either parked passenger side down, accelerating (won't go above 3k rpm) or around a right hand corner.

My workshop manuals are at home (Blackwater) and I'm in Rocky today so could buy the parts. Wondering if there is a hose that could have perished, causing it to suck air instead of fuel as soon as fuel moves to the wrong side of the tank, or if the sender is sitting too high. I imagine there's some sort of pot to give it some surge capacity near the sender unit when fuel moves around the tank.

It's a vz 5.7 Calais sedan.

Thanks
Hobbsy4.
 

07GTS

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when some of those senders are playing up they read higher then actual so u may be close to running out and not really have 1/4 in the tank...
 

hobbsy4

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Thanks for the reply. I thought that, but it only takes 45-50L (aligns with trip computer consumption) so I should have atleast 25L remaining..
 

07GTS

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seems odd must be something going on, the pump modules get fuel from the very bottom of the tank and with 25 litres in there should be no problems, they do use a sorta pot setup which recirculates back into itself so should last for a bit until more fuel comes in...
 

XioiX1983

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I have the same problem (incorrect reading), so I had a new pump/sender unit fitted. Still same problem, I reckon it's a software issue or the shape of the fuel tank.
 

hobbsy4

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The reading was correct, it just lost power with 20L remaining in the tank (I know because the car takes 55L before I can't put any more fuel in). Put in a Walbro fuel pump and sender unit and I no longer lose power and the car starts when it takes 60L. Perhaps I wrecked the pump when I tested how dry I could run the tank (down to 2L) last year, which wasn't a good idea.
 
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