Car sputter when having 1/4 or less fuel tank

[MMamdouh]

Hi guys

one of my friends got a new '05 Lanos 1.5 SOHC and he got this issue... whenver the fuel is less than 1/4 tank the car starts to sputter.

during that the car has no CEL and it performes excelently when having mre than 1/4 tank of fuel so it has to be something in the fuel system... any suggestions?

MMamdouh

[mightywoo]

TRY A FUEL PRESSURE REGULATOR VARIYING PRESSURE FROM FLUCTUATIONS IN FUEL CAUSE INJECTORS NOT TO GET ENOUGH FUEL HAD SAME PROBLEM WITH 98 LANOS

[MMamdouh]

i didn't really get this... do you mean that the fuel pressure regulator is bad??

MMamdouh

[BosnianLanos]

Possibly the fuel pump. Have it checked out. It has enough strength to pull when it is full, but when it is empty the vacuum isn't strong enough. Maybe he isn't tightening the fuel filler cap and the vacuum isn't strong enough. Basically, something might be up with the vacuum in the fuel system.

[MMamdouh]

So basiclly this has to do with one of the following:

1- Fuel pump.
2- Fuel tank cap.
3- Fuel pressure reguator.

i suspected a dirty fuel filter but the guy told me the car is brand new so it is not a possiblity, anyways the car is still under warranty but i wanted to know your opinion so the guys at the dealers don't rip him off and till him any accusations to get away with the free service.

thanks gus for the help and if you got anymore ideas Please share.

MMamdouh

[daewooluvr]

or perhaps the fuel sending unit is bad and he's really running out of gas.

[mightywoo]

the regulator is to give a constant supply of fuel at the required pressure it can be ajusted to suit your style of driving as the woos dont like members of the lead welly brigade also as far as the fuel filter goes dosent matter if car is new the garage you use for petrol might have crap floating in there main tank which in turn goes into yours always wort changing fuel filter only few ??s rather than big problems also have you made eny changes to induction or exhaust may cause problems