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For some time now I have had an issue where as soon as the fuel tank gets to exactly 25% the car starts stalling and I have to pull over and restart it - and it will go another few hundred metres and then do the same thing. Prior to this I had recently replaced both fuel pumps, filter & NRV and have double checked everything a couple of times to no avail.


This week the symptoms suddenly changed, I was running near ¼ tank because I was going to pull the tops of the pumps and try and find the cause, and twice, as soon as it got down to 25% the car stopped and would not restart until I added some fuel to the tank.


Today I started to troubleshoot, first thing I noticed is 2ndry (right hand side) pump is not running when I open the drivers door.


If I remove 2ndry RHS pump fuse (pos 13) & relay (pos 19), the car starts and runs fine.


if I remove primary LHS pump fuse (pos 14) & relay pos 6/1), the car wont start. 


Tried swapping the relays, no difference.


With Primary pump disabled by removing fuse & relay, car wont start or run, but if I remove the secondary pump relay and jumper it, the pump starts running and the engine starts and runs!


So it seems that something is preventing the secondary pump from running, both when the drivers door is opened, and when the tank is at or below 25%. But its not the fuse or relay?? It almost seems like a logic issue! None of the things that should cause the pump to run are doing so.

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