Low Fuel Fault

[unknownspeedster]

Hey guys,

not having much luck with my 2012 D40 (140kw) Auto,

seems to have developed a fault when around a quarter of a tank when you sit at the lights and move off or slow down to a stop the car seems to struggle and kind of shake but as soon as you add some throttle it disappears the other thing is when it cold it seems to idle a bit rougher.

the weird thing is add some fuel and all the fault disappear.....

Nissan service department think its related to the torque converter locking up which doesn't make sense as to why its only developed and only when low on fuel .

i think its fuel pump/filter or injector related hoping someone has had a similar fault or might be willing to add some thoughts to it?

 

[Old.Tony]

The word "idiots" comes to mind when reading that bit about what the dealer said. TCC can't lock unless you're doing over 75km/h in top gear with overdrive active, under 75% engine load (I've noticed that although it's supposed to be 50%, I can lock my TCC at 70% load but can't lock it at 75%).

It more likely the fuel pickup is no longer sitting in the bottom of the fuel tank, or the fuel is foaming as it's returning (possible air leak before the pump?).

It's not likely to be the pump, because the pump is not affected by the level of fuel in the tank. Aeration of the fuel will cause lower tank fuel levels to draw the aerated fuel in more than higher tank levels would. I doubt it's injectors for the same reason - unaffected by tank levels.

 

[unknownspeedster]

Thanks Tony, easiest way to check without having to pull everything apart?

 

[Old.Tony]

Let the car get low on fuel, show signs of the problem and park it for a couple of hours, then pump the primer. Should only get a couple of squeezes in before it's hard - if you get more, there's air in the system.

If not, you'll have to put a piece of clear tube in the line after the filter. It's low-pressure (vacuum, if anything!) so fuel won't go squirting everywhere. Look for bubbles when the engine is running.

 

[unknownspeedster]

i think its a joke you need to do your own diagnostic before giving it to the dealer for them to look at it!

 

[Old.Tony]

If they're suggesting a TCC engagement might be responsible for rough cold-start idling, I'd be finding a different dealer to take it to, to be honest. God knows what they'll do - maybe they'll change the globe in your glove box and hand it back saying "FIXED!!!"

 

[unknownspeedster]

low headlight fluid lol,

going to try to pump the primer when i leave work tonight.

one thing i did noticed on the way to work is that the issue in traffic seems to become less obivious when it dipped below the final quarter mark.

so its seems the sequence of event occurs like this between a full and half tank the car is happy as larry, then the fault appear and on the last quarter isnt so bad. then once you fill it up the cycle repeats.