Question about 1994 Lexus LS 400

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Greetings. I have a 1994 lexus ls 400 the fuel gage goes up very slowly when put fuel in the tank than it comes back down and stay down.

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  • coolnajmi91 Jun 18, 2009

    I have to replace the fuel sending unit Lexus Ls 400 sending unit is inside the trunk right behind the back seat. Gas tank does not have to be lowered unit is aces sable from inside the trunk.

    Thank You you have been a great help.



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HI, this is a malfunctioning sending unit that is located inside he fuel tank. this sending unit, transfers a Resistance signal to the gauge, in return, allowing you to see how much fuel is in the tank. if this mechanism becomes corroded or, damaged, this will cause the symptoms you are experiencing.

This damage is usually caused by fuel deposits left behind overtime. the modern day fuel we use can destroy sending units because of all the detergents and, nitrogen cleaning agents put in the fuel at the refinery. this is goo for cleaning out the rails and fuel injectors but, it usually can hurt the sending unit mech at the same time.

The fuel gauge sending unit is attached to the fuel pump Assembly. you will have to remove this assembly from the tank to replace it. the tank has to be lowered as well.

Posted on Jun 18, 2009

  • Michael Masters
    Michael Masters Jun 18, 2009

    Ok, good deal. i did some further research on the accessible regions and, it says that you can access it this way. this is way more efficient than lowering the entire tank.

    Thanks for the update.



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