Timakle

Hey whats good cl.
I been noticing lately everytime my car is low on gas
It starts misfiring and shaking And the problem seems to go away when i fill up the tank. I always use 93 octane and dont let the gas come all the way to empty i usually fill up when the light comes on. I also use a fuel injector cleaner now and then. I really dont know if is a vacuum leak or is a ignition coil but im not getting any cel.
Thanks.

KenMasters

UZ or JZ motor?

Timakle

2jz vvti. My bad

Arcadian

Could be contaminated fuel. I filled my old Sunbird at Shell,then a few weeks later they announced that they had sold contaminated gasoline. My car started to stumble when the gauge was just above empty. The contaminant was particulate and tended to settle, so when the fuel got low the it would get in the line. That's my experience - different car of course.

dejavu157

iTrader: (2)

if a gas station sold u bad gas, are they responsible?

KenMasters

This is a tough one, If you have access to a wide band 02 you can tell for sure but it sounds to be running rich. have you noticed the smell of gas or seen any puffs of smoke?

Timakle

No smoke no gas smell or nothing i really think it has to be something with the fuel tank cause it only does it when its low on gas

aprince1

iTrader: (5)

Start by replacing the fuel pump and filter. Could be the pump stuttering while working hard on empty or there are particles in the filter that hinder the performance.
Also do you feel the car misfiring or hesitating? If its misfiring you can hook up a code reader and get more information.

Timakle

Im gonna check to see if i can pull any codes with the scanner.

fuzzzz

iTrader: (19)

I ALWAYS pump shell, when was this?!


If you can prove that you went to shell to pump gas and prove that the bad gas damaged your engine, you have every right to sue

daihap133

To check for vaccum leak, do this at your own risk: Get a can of propane, connect a small hose to the outlet of the propane, start your car, open the valve of the propane and put the end of the hose near the area(throttle body, intake manifold, hose fitting..etc) where vaccum leak is possible, scan these areas by spraying propane to it, if you hear a noticable increase in RPM(you can hear it), that is where the vaccum leak is.

KenMasters

^carburator cleaner will do the same thing, only stall instead of rev.

Timakle

i check for any vacuum leak but couldnt find any, then i added some marvel mystery oil i was told by a friend of mine that if it was a clogged injector that would help but still no luck yet the car still has the little "heekcup" not as much as before but still doing it.

daihap133

Few things you can check:

1/. Gas cap, if there is any cracks in it.
2/. Fuel pressure, hook a fuel guage to the fuel dampener port in the fuel rail.

If the fuel pressure is above 44-50 psi, replace the fuel pressure regulator.
If the fuel pressure is below 44-50 psi, it could the fuel pump, one or more of the three 0-rings in the fuel pump assembly is bad, or the fuel pressure regulator is bad.

3/. Or it can be your fuel filter is dirty, when the gas is low, it cannot sipon enough gas to the engine.

I would replace the fuel pump, fuel filter, the three 0-rings in the assembly, you can get the pump from ebay for about $100-200, fuel filter about $30 and the 0-rings, two of them are the same and I think lexus doesn't carry them, you have to get it from the Toyota dealer. Take a look at this thread, it has a lot of discussions about that O-ring:

https://www.clublexus.com/forums/gs-...-searched.html

Timakle

thanks for the info. i look it up.