Warning Light Of Diesel Tank

[JohnYossarian]

Hello all,

I have been thinking of posting on this topic for almost two years now.

I have always filled the tank to the top. This way I can calculate the consumption far better than the on board computer.

Last night the orange warning light popped up at 525 miles done and IIRC this usually means that I have about 40 miles left in the tank before I run dry.

I went to the nearest Shell station and put 51.5 litres of diesel. As far as I know the Avensis (TX30 D4D 2.0) diesel tank is 60 l. Simple math tells me that I should have had almost 9 l left and yet the light went on.

It has happened before.

Can anyone enlighten me on whether the tank is somehow dirty (I cannot believe that I would have almost 5 l of dirt) or is it the sensor that does not register the amount of fuel left properly?

The car is very close to what Toyota predicts in terms of consumption. Average combined is often in high 40 and low 50 mpg.

Thanks!

[200hp]

Hello all,

I have been thinking of posting on this topic for almost two years now.

I have always filled the tank to the top. This way I can calculate the consumption far better than the on board computer.

Last night the orange warning light popped up at 525 miles done and IIRC this usually means that I have about 40 miles left in the tank before I run dry.

I went to the nearest Shell station and put 51.5 litres of diesel. As far as I know the Avensis (TX30 D4D 2.0) diesel tank is 60 l. Simple math tells me that I should have had almost 9 l left and yet the light went on.

It has happened before.

Can anyone enlighten me on whether the tank is somehow dirty (I cannot believe that I would have almost 5 l of dirt) or is it the sensor that does not register the amount of fuel left properly?

The car is very close to what Toyota predicts in terms of consumption. Average combined is often in high 40 and low 50 mpg.

Thanks!

hi john i wouldnt b worried about the fuel light i used to have a 92 corolla, in that the fuel light came on with 10litres to go in the tank which would give me around 40 miles until empty aswel. I now have a heavy modded levin and the fuel light comes on around 8 litres to go. the reserve light sensor can also be triggerd by fuel mooving around at a low levil. hope that helps. Ryan

[igormus]

Hello all,

I have been thinking of posting on this topic for almost two years now.

I have always filled the tank to the top. This way I can calculate the consumption far better than the on board computer.

Last night the orange warning light popped up at 525 miles done and IIRC this usually means that I have about 40 miles left in the tank before I run dry.

I went to the nearest Shell station and put 51.5 litres of diesel. As far as I know the Avensis (TX30 D4D 2.0) diesel tank is 60 l. Simple math tells me that I should have had almost 9 l left and yet the light went on.

It has happened before.

Can anyone enlighten me on whether the tank is somehow dirty (I cannot believe that I would have almost 5 l of dirt) or is it the sensor that does not register the amount of fuel left properly?

The car is very close to what Toyota predicts in terms of consumption. Average combined is often in high 40 and low 50 mpg.

Thanks!

Hi mate

the problem might be simple -- connected with sensor failure due to continue driving on 1/4 of the tank or less.

In case you used to filled in a good diesel -- no doubts you have no 5 ltr of dirt deposits.

In any case you have to inspect condition of this sensor. Cheers/Igor

[hertsnminds]

Were you travelling or parking on a hill when the car gave these different from normal readings? I have had one car where if you parked it on a slope with the drivers side higher than the passengers then your fuel reading would increase for the next couple of hundred miles. In the Verso I have had the yellow light come on at the end of a journey only to be off the next time I start the car. It could be related to how the fuel is moving about in the tank and also how much pressure is in there. You could try just opening the fuel filler to let some air in (you sometimes hear a whooshing sound with a near to empty tank) and see if that makes a difference.

[OldSkoO1]

Were you travelling or parking on a hill when the car gave these different from normal readings? I have had one car where if you parked it on a slope with the drivers side higher than the passengers then your fuel reading would increase for the next couple of hundred miles. In the Verso I have had the yellow light come on at the end of a journey only to be off the next time I start the car. It could be related to how the fuel is moving about in the tank and also how much pressure is in there. You could try just opening the fuel filler to let some air in (you sometimes hear a whooshing sound with a near to empty tank) and see if that makes a difference.

I haven't seen the design notes but i'm fairly sure that toyota are very conservative with the low fuel warning lights. The diesel fuel is used to cool and lubricate the fuel pump.

If you are low on fuel the pump has to work harder to find the remaining fuel which can heat up and stress the pump. Constant abuse like this can lead to earlier failure.

I believe it's just another safety net toyota have built into their design.

[t-spiritpete]

Hello all,

I have been thinking of posting on this topic for almost two years now.

I have always filled the tank to the top. This way I can calculate the consumption far better than the on board computer.

Last night the orange warning light popped up at 525 miles done and IIRC this usually means that I have about 40 miles left in the tank before I run dry.

I went to the nearest Shell station and put 51.5 litres of diesel. As far as I know the Avensis (TX30 D4D 2.0) diesel tank is 60 l. Simple math tells me that I should have had almost 9 l left and yet the light went on.

It has happened before.

Can anyone enlighten me on whether the tank is somehow dirty (I cannot believe that I would have almost 5 l of dirt) or is it the sensor that does not register the amount of fuel left properly?

The car is very close to what Toyota predicts in terms of consumption. Average combined is often in high 40 and low 50 mpg.

Thanks!

Hi John, no worries that is normal, also you can get a few extra ltrs in by filling the tube that leads to the tank so that's more than 60 ltrs!

Best regards Pete.

[Thermal]

Hi, don't worry.

The other day, my petrol warning light came on when the computer indicated there were 28 Km left in the tank.

I kept driving for another ~60 Kms, when the wife became really nervous.

So I stopped at the next petrol station and I spent a couple of minutes trying to fill the tank past the "Auto stop" until I finally saw petrol in the filling tube.

I managed to get only 49.81 liters into the 60 liter tank.

I have a 10 liter jerrycan somewhere, and one of these days I plan to run the car dry.... just to see what the content of the tank really is.

BTW, mine does 6.6 L/100 Km according to the computer, and 6.8 L/100 Km according to me.

Convert to miles and mpg as necessary. ;)

[JohnYossarian]

Thanks guys for all your replies!

It was extremely useful to learn that the diesel pump should not be put under stress by driving at low tank level.

I usually steer clear from driving with the tank less than 1/4 full. I have always had the feeling that this way I am increasing the risk of the injectors and any other part sensitive to fuel contaminations, getting blocked. I know that there is a fuel filter but it is better if you keep the system clean.

@Thermal. Mine does 6 l/100 km and this is what I call "not that good" combined driving. This corresponds to 47 mpg.

Cheers!

Jordan

[jimrotts]

not a very good idea running fuel tanks to low as this can lead to debris from the tank being drawn into fuel lines and into filter but the biggest danger is it causing fuel lift pump to seize up which can lead to expensive repair and a unneccesary ride in recovery truck

the trip computer is not meant to be accurate only a guide the gauge in the dash should be relied on for accurcy

and fuel consumption has to many variables to calcute

eg load and speed and tyre pressures have a very real causes for variation also weather conditions , types of road andcondition eyc

[Thermal]

not a very good idea running fuel tanks to low ...

You are absolutely right.

Deliberately running the tank dry is not a good idea, specially with diesel engines where the diesel is supposed to lubricate the pump(s).

What I intend to do is, have my jerrycan filled, just in case.

Then, with my calculated theoretical range of 882 Km, minus 32 Km safety which is ~20 miles, see what I can get into the tank.

My petrol Avensis is still fairly new, so I don't expect debris in the tank.

I will let you know some time.

My previous car, not a Toyota, was specified with a 70 liter tank.

I managed to fill it once with 72 liters though. :o

That was unplanned, because the planned petrol station was closed down.

Anyway, always good to know the real tank capacity.