Hello,
I am getting used to my 2nd 99 GS4. I have had this one for about 1 month, and it is in very good shape. I guess my biggest pet peeve on the car is the inaccuracy of the fuel guage. I began to notice that the fuel guage moves away from "FULL" very quickly after a fill-up. In fact, I have noticed that the guage begins moving at about 26 miles from full on the ighway, and faster aroud town.

The fuel light also comes on right at 1/4 tank. Yet when I fill, it barely takes 14 gallons. My questions are:

1..Has anyone else had this problem with your car?

2. What did you do to repair it?

3. Can an inaccurate guage be re-calibrated by the dealer?

On the road, this is a very aggravating phenomenon. It made me think that something was wrong with the engine / emission system. Now that I know that the fuel consumption is normal, I may have to replace the in-tank fuel module, or something like that. Any suggestions would be welcomed and appreciated.

Thanks again!

 

my 98 ES3 has that problem. Fill up the tank and it takes quite a while for the needle on the fuel guage to rise to the top. THe needle is brutally inaccurate too. Ill be sitting there with my car at idle for say... 5-8 minutes and the tank will drop 3 or 4 knotches. it wasn't that big of a deal to me tho so i never really looked into fixing it.

 

Yes,
It bothers me to have the guage so inaccurate, but I'll try to live with it. It can be either the fuel guage itself (unlikely), or the float and resistor assembly in the tank. Either way, it will cost some money to fix, and I will have to decide how much money I want to spend on this.

 

gserep1, the dealer can't not recalibrate your gauge. But they can hook up the scan tool and run the active test to check the gauge.

They can select from the main menu on the scan tool, select ' OBD' and select vehicle and year.

Then, they can scroll down to ' Meter', select the Fuel Gauge and the can use the arrow key on the scan tool to make the gauge goes from ' Empty','1/2' ore ' Full'. If the fuel gauge is working fine, it will go from empty,1/2 or whatever the tech wants it to be. This will tell you the problem is from the sending unit inside the gas tank.

I don't know how much they will charge you to do this, but is as easy task. Or you can ask one of the tech to do it for you and pay him on the side.

 

I thank you for the good info. I will contact the dealership and see if they can do this for me. I guess only the dealer has that tool, so I will be forced to go to them. That is like pulling teeth....not very nice. I will keep everyone posted on how much this is going to cost!

 

My guess is that you are one of the first to experience what is going to turn out to be a bad resistor on the circuit board that the instrument cluster is controlled by. If this is anything like the problems older LS 400's have the gauge will go from innaccurate to not reading anything as the resistor continues to deteriorate.

damon

 

That why I told gserep to go to the dealer and ask them to do the active test.This way he knows the preblem is from the gauge or from the sending unit.

 

I am scheduled to have the fuel guage looked at on Friday, 9 July at my local Lexus Dealership. The cost will be $90.00, and that amount will be deducted from any further repair work to be done. If it is the sender, I can do that myself because I heard that to have them do it will be about 400 dollars. NOT HAPPENING with me.

 

I'm having the exact same problem with my 98 GS 400. I fill the tank and very soon after the gauge starts going down.
I just bought this car and I'm thinking the O2s are bad and its getting horrible mileage, but maybe its something else altogether.
I'm at a half tank right now and the trip odometer only reads 100 miles!!!!!!!

Please let me know what you find out.