99 Rx300 Knocking After Running Low On Fuel

[azam_butt1]

I have a 99 RX300. MY wife went very low on fuel yesterday and by the time she got to the gas station the Car started Knocking. She put Gas in it and she started driving it. The car knocks untill it gets up to 35mph after that it runs smooth. Any Ideas on what could be causing this and what do I need to do. Any help would be appreciated. Thanks

[ColinBarber]

Could try resetting the engine ECU. With the ignition off, remove the EFI fuse from the engine bay fuse box for 30 seconds .

[azam_butt1]

Could try resetting the engine ECU. With the ignition off, remove the EFI fuse from the engine bay fuse box for 30 seconds .

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Here are some details

Car only knocks when you put it in Drive. If you leave it idle it works fine.

Car only knocks up to 35 to 40 mph and after that it runs smooth.

Some one at the dealership told me it could be fuel pump or fuel pressure regulator.

Any Ideas?

[RX in NC]

Running any fuel-injected vehicle's gas tank to "empty" on your gauge is always a bad idea. You run the risk of getting air or fuel tank "grit" into your fuel lines which can create a myriad of problems from ruining your fuel pump to clogging your injectors. Fill your tank and try some fuel injector cleaner additive to see if that makes a difference for you. If it doesn't, the next step may be to have your fuel system professionally cleaned. If that doesn't do it, then you may have to replace your fuel pump.

The moral of this story is to never let your gas tank get below a quarter full.

[SKperformance]

true

unlesss you always go right to the bottom of the tank everytime

air is no problem even if it was it would sit in the fuel rail above the injectors and be siphoned off to the return lines.

[TunedRX300]

I know some car use gasoline to cool fuel bump, not sure about RX though. If it is the cause, another reason not to run out of gas.

Not sure about fuel deposits clogging it since road bumps, accelerations, and braking stir up everything in our fuel tanks routinely.

[ColinBarber]

Not sure about fuel deposits clogging it since road bumps, accelerations, and braking stir up everything in our fuel tanks routinely.

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That's why there is a fuel filter.

[TunedRX300]

Not sure about fuel deposits clogging it since road bumps, accelerations, and braking stir up everything in our fuel tanks routinely.

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That's why there is a fuel filter.

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Exactly, I meant fuel pump won't be clogged due to the level of gasoline in our tanks. Sorry if I cause confusion...

[azam_butt1]

Not sure about fuel deposits clogging it since road bumps, accelerations, and braking stir up everything in our fuel tanks routinely.

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That's why there is a fuel filter.

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Exactly, I meant fuel pump won't be clogged due to the level of gasoline in our tanks. Sorry if I cause confusion...

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well here is what I did. Hooked up the PC to find out the errors and it gave me 3 different errors about fuel mixture being too rich and misfire in Cylinder 4. I just picked up Vavoline Sync Blend Fuel system cleaner and poured it into my tank and filled it up and beleive me or not with in 2 miles of driving every thing became normal. Now car is performing perfect with out any problems. Thanks for every ones help.