'02 Avalon Fuel Sender

[JohnG]

First time Toyota owner, I've just bought an 02 Avalon Grande (and loving it!). So far I've only found one fairly minor fault with it. The fuel gauge reads fine till it gets down to about a quarter, after which it does a nose dive. The distance to empty can drop from about 140 or so down to 20 or less, rapidly followed by the low fuel light coming on. I figure this is due to a problem with the fuel sender unit.

I've been able to grab some electronic copies of US workshop manuals for the Avalon and Camry but none show the fuel tank or sender. How big a job is it one these cars? Do I need to drop the tank or is it accessible from the boot? I haven't had an opportunity to look at it yet, so any pointers will be appreciated.

In the event that I cannot repair the unit myself, how much should I expect a replacement to cost? So far I've had wreckers quote anything from $110 to $165, which to me seems an absurdly high price for just a sender.

[450HP/tonne]

First time Toyota owner, I've just bought an 02 Avalon Grande (and loving it!). So far I've only found one fairly minor fault with it. The fuel gauge reads fine till it gets down to about a quarter, after which it does a nose dive. The distance to empty can drop from about 140 or so down to 20 or less, rapidly followed by the low fuel light coming on. I figure this is due to a problem with the fuel sender unit.

I've been able to grab some electronic copies of US workshop manuals for the Avalon and Camry but none show the fuel tank or sender. How big a job is it one these cars? Do I need to drop the tank or is it accessible from the boot? I haven't had an opportunity to look at it yet, so any pointers will be appreciated.

In the event that I cannot repair the unit myself, how much should I expect a replacement to cost? So far I've had wreckers quote anything from $110 to $165, which to me seems an absurdly high price for just a sender.

Sorry to bear the bad news, but that's how they are designed.

Full means you have enough fuel and empty means you've driven too far without stopping for a drink. Everything between is just an image and is not a linear correlation of litres of fuel remaining.

I took a photo of my Aurion when it was new, showing 438.6 km travelled and 290 km cruising range ... Yet the gauge was at the half way mark. My economy was 7.82 by the end of the trip, so a range of 895 km from 70 litres. From there it starts to drop quicker and quicker, and the cruising range leaves lots in hand (166 km in my case).

Any repair or replacement will not help, unless you get really serious and design your own sensor. They are not designed to be serviceable.

[JohnG]

Sorry to bear the bad news, but that's how they are designed.

Hi 450HP/tonne.

Thanks for the reply but it appears I may not have been completely clear about the problem. When I say the gauge does a nose dive I mean it drops almost instantly when it gets to a certain point. It's not the normal non-linear drop that is the result of the tank shape and other factors. I'll be getting LPG fitted in about a week and a half, after which I will be able to attack this little problem properly.

[450HP/tonne]

Sorry to bear the bad news, but that's how they are designed.

Hi 450HP/tonne.

Thanks for the reply but it appears I may not have been completely clear about the problem. When I say the gauge does a nose dive I mean it drops almost instantly when it gets to a certain point. It's not the normal non-linear drop that is the result of the tank shape and other factors. I'll be getting LPG fitted in about a week and a half, after which I will be able to attack this little problem properly.

Now I see why you asked ...

In the Aurion, the sender unit is part of the fuel pump assembly. It involves removing the rear seat cushion, some sheet held on by butyl and then some screws. The Aurion contacts are exposed and could be cleaned or you cold perform a test on it (just be sure to have the pump isolated if you switch the ignition on!). Other than that, the sender is not serviceable (again, for Aurion).

Check the manual you have and follow the fuel pump removal procedure would be my advice. Find out what's causing it and clean or replace as required.

If the sender is part of the pump assembly, this may explain the cost ...

[JohnG]

Sorry to bear the bad news, but that's how they are designed.

Hi 450HP/tonne.

Thanks for the reply but it appears I may not have been completely clear about the problem. When I say the gauge does a nose dive I mean it drops almost instantly when it gets to a certain point. It's not the normal non-linear drop that is the result of the tank shape and other factors. I'll be getting LPG fitted in about a week and a half, after which I will be able to attack this little problem properly.

Now I see why you asked ...

In the Aurion, the sender unit is part of the fuel pump assembly. It involves removing the rear seat cushion, some sheet held on by butyl and then some screws. The Aurion contacts are exposed and could be cleaned or you cold perform a test on it (just be sure to have the pump isolated if you switch the ignition on!). Other than that, the sender is not serviceable (again, for Aurion).

Check the manual you have and follow the fuel pump removal procedure would be my advice. Find out what's causing it and clean or replace as required.

If the sender is part of the pump assembly, this may explain the cost ...

Thanks for the info. I would have been wasting my time trying to get at it through the boot. :) At least I won't have to drop the tank.

If the innards of the sender still use the same "technology" as every other car I've ever had it might be a simple matter of re-spacing the wires that the wiper sweeps (much like the wires in a toaster element). Of course my luck tends not to work that way.