Guys,

my LS 430 UL 2003 started to behave weirdly yesterday.
First the VSC Off panel light was on all the time. I have run a scanner tool and it seems it was requesting me to do a Zero Point calibration.
When I was driving back home, the car suddenly stopped, the red battery icon showed up and the steering wheel got locked, in the middle of the road. I pulled the car aside, waited 5 minutes and turned it back on without problems. Drove for 2km, and the same thing happened again. This time I was few meters from my house so I waited few minutes, turned the car on again and parked it in my garage.
After leaving the car untouched overnight, I turned it on again this morning and also connected my odb Bluetooth scanner. I left the engine on for around 10 minutes and gear in the P position. The RPM needle stayed constant at 850RPM and after a while starting oscillating between 0 and 1000 RPM until it died.
Tried to turn it on again without success. It produces the normal noise of trying to start the engine, but it never finishes the process.
I have attached an audio file so you guys can listen to.
I have also attached the screenshots of the ODB codes I got from the apps.

The yellow fuel reserve light is on, and the dashboard says I have 64 miles range left, so I doubt it is lack of petrol . However, the fuel gauge has been imprecise since I bought this car. When I have a full tank, it shows that I have 3/4 of a tank only.

Any ideas of what could be the problem?


Carbit ODB app

Thinkdiag

Thinkdiag

 

Have you verified the health of the starting battery and the alternator? I would also rule out lack of fuel by adding a few gallons of fresh fuel to the tank.

 

Sounds like it's out of fuel.

 

+1
It seems to me that the fuel pump is weak or the fuel filter is badly clogged. One idea is to bypass the fuel pump resistor short-circuiting the resistor's connector or short-circuiting the pin #3 and #4 of the fuel pump relay. But this is only the confirmation. You probably need to replace the fuel pump unit which is consisting of the pump motor and the filter.

 

Hi Guys,

Thank you for chiming in. I have tested both the battery and alternator and they were just fine. So I did the quick test suggest here. I went to the gas station and bought 5 liters of gasoline. It did the trick!
The tank was totally empty.
The curious thing is that the dash showed that the car has 64 miles range left as you can see in the attached picture ... And I trusted it ... The yellow LED dot showing the car was in fuel reserve mode only turned up when the tank was already empty

Any ideas what the problem could be?

Thanks in advance!

 

You may have a problem with the float or sending unit in the tank. Your dash is getting faulty information, obviously. If you do some searching you will find posts dealing with gas gauge not reading correctly in a LS 430 and there is a troubleshooting write-up on it somewhere on here.

 

Thank you. I will research the forum for this particular problem. I will let you guys know if I can get this fixed.

 

https://www.clublexus.com/forums/ls-...e-problem.html

 

Sounds like an grounding problem to me. The LS has a plastic gas tank, so make certain that your fuel sender has a good quality ground connection.
In the meantime I'd recommend putting a 5 gal tank of gas in the trunk, just in case.

 

Thank you very much for sending this file . The car is currently at Lexus for preventive maintenance (timing belt replacement, transmission filter) and also replacing one defective O2 sensor. They will check the fuel gauge problem as well. Let's hope they can fix it .

 

Interesting. I will definitely take a look at it at Indy workshop with Lexus cannot fix it.

 

Hi all,
Just a quick update on my end.
Finally, I picked up car at the dealership today. It took a long while to get the parts needed from abroad.
Both fuel gauges were defective and needed to be replaced by brand new OEM ones (part #83320-50080 and #83320-59125).
They have also replaced two O2 sensors (downstream) as per the error codes showed on the scanner tool. I can't believe that annoying CEL sign is finally off!
Because the car was at Lexus for over a month, I asked them to replace all spark plugs with new iridium ones and both the VSV and PCV parts with OEM ones.
With all those changes plus a new timing belt, transmission filter and transmission oil, I feel I the car is good for the long run as a daily driver.

Next "project" is to get rid of all those tiny rock chips that drive me nuts and a cold air intake.

thank you to all of those that chimed in and helped me out.