Low Fuel Light On Dash Even When I Put £30.00 In All Other Items On Da

[Dale_V]

yes please give up, because real world experiences count, not theorys with maths. I've ran on fumes in the ls400 to the point the engine has actually misfired due to fuel starvation, I think if I remember correctly I then put £20 in, the fuel light went out... £30 will sort the light good and propper.

Jeeze, yeah "if I remember" and if petrol was as expensive then as it is now. Are you just making up new stories as you go along?? This story would've been infinitely more useful at the beginning of this thread than the fact £30 is not a third of a tank, and £110 is not a fumes to brim fill up.

Just fill up and see if the light goes off, how can it be so difficult :)

Have fun

I thought you was giving up? It was last year, no need to make up the stories, whats the point in that? I KNOW how much fuel does what in an LS400, I have one for chr1st sake, I dont have to work on pathetic maths theories.

£30 IS a 1/3rd of a tank from the bottom line, theres no two ways about it (not from below, not from above the empty line)

Just fill up and see if the light goes off, how can it be so difficult :)

Have fun

Jesus holy *****, if he has put in £30 the light should have definatly gone off, by filling up it will only be by luck if the light dissapears, due to the sender possibly being dislodged, It wont have been because there was a lack of fuel and the light being genuinly on

Which part of your brain can't understand £30 is enough to get rid of the fuel light, be it from the bottom marker of the fuel guage or from a bone dry tank!

[phil2009]

If the OP was running on fumes 10 litres of fuel would be enough to extinguish his low level light, it might come on again with in 5 miles or so but defo would not need anywhere near £30, and thats without doing the maths.

How do you know 10 litres is enough?

I cant believe so many people are trying to get this guy to spend money on a repair that may not be needed for the sake of another trip to the petrol pump.

Why I know???

30 yrs driving various cars covering 60k miles every year,

28yrs as a toyota technician,

10 yrs as a Lexus Technician,

Owned 3 Lexus

Fixed and road tested 100's of Lexus,

Forgot how many cars on road test I have had to put 5litres of fuel in when I have seen the light on.

Untold amount of breakdowns when run out of fuel at roadside,

I could go on and on.

Sorry Tigerfish, I am not after a argument but I was just replying to your post that seemed a bit forceful

[ROCKINBAZLS400]

hi a i am brand new lexus owner ( had 7 series for ten years ) car has just had a health check from lexus main dealer and when i filled up with £30.00 of petrol the low fuel light still stays on , rang lexus and the guy said the float has probably stuck ... help what do i do ... baz in bolton

I had a similar problem with the sensor for the windshield wiper fluid - it took me a very long time to fill it up but even overflowing it was still showing the empty light. Lexus suggested replacing the sensor (a little over £100 just for the sensor so I passed up the opportunity). Several months later, for no apparent reason it fixed itself! Of course I do realize that with the fuel gauge it is quite critical. Personally I would fill up the tank to the brim and this might just move the float off. (yes, there is the matter of the cost - if really low figure somewhere between £80-£90, ouch!) If it doesn't I would guesstimate about 300 mls (to be on the safe side) on a full tank. To bear in mind that if you were running on empty £30 would not make a huge difference. No doubt, one of the more technically-minded guys on here might have better advice. Welcome to the LOC and enjoy the ride!HI AND THANKS FOR THE ADVICE, PENSION DAY ON MONDAY, SO I JUST MIGHT DO THAT , ITS FUNNY ALL THE TIME I HAD THE 7 SERIES ,I NEVER PUT PETROL IN TILL THE WARNING LIGHT CAME ON , BUT I DO LIKE THE LEXUS ITS SO QUIET , CHEERS BAZ IN BOLTON

[ROCKINBAZLS400]

If the OP was running on fumes 10 litres of fuel would be enough to extinguish his low level light, it might come on again with in 5 miles or so but defo would not need anywhere near £30, and thats without doing the maths.

How do you know 10 litres is enough?

I cant believe so many people are trying to get this guy to spend money on a repair that may not be needed for the sake of another trip to the petrol pump.

Why I know???

30 yrs driving various cars covering 60k miles every year,

28yrs as a toyota technician,

10 yrs as a Lexus Technician,

Owned 3 Lexus

Fixed and road tested 100's of Lexus,

Forgot how many cars on road test I have had to put 5litres of fuel in when I have seen the light on.

Untold amount of breakdowns when run out of fuel at roadside,

I could go on and on.

Sorry Tigerfish, I am not after a argument but I was just replying to your post that seemed a bit forceful

HI ITS BAZ IN BOLTON , I THINK I WILL LET IT GET TO WHERE THE LIGHT COMES ON THE PETROL GAUGE AND THEN PUT £50.00 IN PITY YOU DONT LIVE IN BOLTON ,I COULD DO WITH A FRIEND THAT KNOWS LEXUS LS 400 ALL THE OTHER ITEMS ON CHECK LIST FINE, I DID LOOK FOR A LONG TIME TO FIND THE RIGHT CAR ITS ONLY EVER BEEN SERVICED BY LEXUS, ITS JUST ODD , AS WHEN I TOOK IT INTO LEXUS FOR A FREE ! CHECK OVER AND THEN I PT IN THE £30.00 AND THE LIGHT WOULD NOT GO OUT ,IT MAKES YOU THINK THEY MAY HAVE DISTURBED SOMETHING , THE ONLY FAULTS THEY COULD FIND WERE A WORN wiper blade AND THE DRIVE BELT HAD SLIGHT WEAR ... BEST MONEY I HAVE EVER SPENT ON A LUXURY CAR CHEERS FOR ALL YOUR ADVICE BAZ IN BOLTON 07851732747

[TigerFish]

pathetic maths theories.

Which part of your brain

£30 IS a 1/3rd of a tank

Fair enough. Without wanting to kick the arse out of this, and to avoid any proper name calling or insults to come out........

tank capacity as stated above is 85 litres.

One third of that would be 28.333

£30 divided 28.3 litres is £1.06 per litre, where have you been able to get fuel at that price? It clearly shows that £30 will not get you a third of a tank full. level shown on the guage does not alter how much petrol you actually have, the capacity of the tank, or how much you get for your money. I'm not sure how this is pathetic maths, it is just how it is

..... and irrespective of lights staying on or off of course <<passes the olive branch>>

[Dale_V]

man, such hard work, but you would know what the guage shows, I mean you can see it in your LS400 :) oh thats right you dont have one, so how the hell can you tell me what my tank is showing at £30 of a fill from the bottom line on the guage? you CANT :)

and from your calculations above, you have not listened one bit to what I said in my 2nd and 4th post

* read the parts highlighted in bold, please for dear god read the bit in bold!

[TigerFish]

you have not listened one bit to what I said

Ditto :)

[Dale_V]

you have not listened one bit to what I said

Ditto :)

well Yes I have, I stated if i fill up from the bottom line on the guage with £30 I get a 1/3rd showing on the tank, yet you have gone and done calculations from a completely full 85 litre tank and divided it by 3, which by doing that at empty the guage would read below the bottom line and at full read above the top line. I never stated I could fill up from completely bone dry empty with £30 and id be a 1/3rd full, I said from the bottom line on the guage!

[Dale_V]

im gunna play that maths game, just for you lol....

So for current fuel prices at £1.34 a litre x 1/3 of a tank (28.3litre) (85litre tank, from bone dry)

1.34*28.3= 37.92

£37.92 for a genuine 1/3rd of a tank, so it is very plausable that from bone dry to the empty/bottom line there is £7.92 (5.9litres) in there, then from the bottom line to 1/3rd showing on the guage there is £30's (22.3 litres) worth :)

1.34*85 = £113.76 (full tank) so I wasnt far out when I said I filled up with £110 to the brim, by that you can also see how low I am running the tank down if I managed to put £110's worth in!!! ....roughly 2.8 litres of remaining fuel

[lexynik]

tigerfish is entirely correct - every car functions differently and no one else even remembers the original question which tf has at least offered a valid suggestion to - op fill your ls up and see what happens

[toxo]

and if I remember right it is not float related but a thermister inside the tank unit that alters its resistance when it is cooled by the fuel

Correct, most Toyotas use the same system - the gauge is a float and the low fuel light warning is a thermistor on a separate arm.

I've found the thermistors to be quite voltage sensitive, if you have a crappy alternator or a dead Battery and have to jumpstart the car a lot they tend to die! Don't ask me why but that is my experience.

The part for the LS400 is about £100 from Lexus and is part number 83320-80360. I think I've got one lying around somewhere.

[beavisrules]

well if it's a mk4 , you could just go by the 'range' on the dash rather than the fuel gauge (if its a differnt sensor?).

empty light comes on at 68 miles left , and says "DANGER WILL ROBINSON" or something at about 22 miles left.

if as BAZ FROM BOLTON says , his '98 has 49 miles range left , it would have beem about 1/2 way between empty and 'seat of pants' empty.

[abs66]

But thanks for the chuckle.

Back on topic

Baz just stick another £20 in if you can and assuming you haven't gone far since the £30 fill. If that doesn't shift the light then follow the other very good advice you will find on this brilliant forum and please let us know how you get on, theres nowt worse than not knowing the outcome lol.

Just for your info my MK3 goes over 1/4 of a tank on £20 from the light coming on, can't be arsed working anything out but I do understand where Tigerfish was going with his maths, I also get the other side too. Splintered arse time lol.