Fuel gauge - inaccurate - adjust or fit warning light?

[agentdagnamit]

Hi

I'm on my second Bongo, I realise the fuel gauge isnt the best, but the new one seems even less accurate than in my previous Bongo.

I can put about 45l in the tank when the gauge is showing under 25%. I know I get about 8 or 9 km to the litre, so should be able to drive between 550 and about 600 km on a full tank - I usually refill after around 450 max.

I took the plastic shield of the instrument panel today, and noticed that the fuel gauge can be nudged in either direction, I guess this is a very rough way of recalibrating?

Alternatively, is it easy to fit a warning light? Now that I have accessed the back of the instrument panel (to change a dashlight bulb) I know that bit is straight forward.

Thanks

[Simon Jones]

There's a really common problem that affects diesel Bongos where the earth connection on the tank fails so the needle will remain at whatever point it was when the connection was last present. Loads of info on how to add an extra wire between tank & chassis which will probably solve your problems.

Fitting an aftermarket low fuel light kit will not work unless the tank sender is working correctly so try the earth mod. If you've got post 1999 model, it is likely to have a low fuel light as it was fitted as standard after that time.

[agentdagnamit]

Thanks. My Bongo is petrol and must have been a little early for a warning light.

Is the light obvious when it isn't lit?

[Simon Jones]

Ah, now if its petrol, that changes things . The petrol tank has a built in pump so there is a beefed up earthing connection for the motor, so in your case if the engine runs ok then the earth wiring is good. If you have a light, it should be amber & it will probably come on briefly when you put the key in the ignition to confirm the bulb is ok. However, don't rely on there being a working bulb to tell you when to refuel in case it does not come on.

[haydn callow]

45lts to fill when showing 25% sounds about right for a 65ltr tank ??

[agentdagnamit]

Sorry, that wasnt very precise, there was about 20l left in the tank when my fuel gauge was starting to look dangerously low.

Maybe I should just go by km driven since topping up.

But these kits seem cheap and fairly easy to fit: http://www.autolinkmx5.com/warning-ligh ... 7318-p.asp

[Simon Jones]

If you fill it to the brim, does the needle go fully to the end of the scale? The gauge is non linear so it will go down quite fast and then slow up as the tank empties as you need the accuracy at the bottom of the scale rather than at the top.

[Tony x]

I've had 3 fuel gauges and they've all read different.
I'm not talking the position of the needle on the scale, the rate at which they went through the different parts of the scale varied and by a fair bit. Only one was reasonably linear.
You could try a second hand gauge and take your chances.

[mikeonb4c]

If you fill it to the brim, does the needle go fully to the end of the scale? The gauge is non linear so it will go down quite fast and then slow up as the tank empties as you need the accuracy at the bottom of the scale rather than at the top.

Oh yea? Mine's the opposite! In the end, none of it matters as much as simply knowing your gauges characteristics and planning accordingly.

[Diplomat]

The only time the needle on my gauge seems to linger in any sector is when the engine is switched off.

I make a point of filling up when it is down to 1/3 of the scale. If you let it go much further it costs far more!


Frank

[agentdagnamit]

When I fill up the needle goes almost beyond the right hand most marker.

Yesterday I ran the needle all the way down to the left, drove another 50k or so, and could still only refill with 51 litres - but that is the most I have ever been able to top up.

This means I have a safety margin of around 15 litres or at least 120km when my gauge reads absolutely empty, which is a bit too much for me.

[Simon Jones]

Surely it's better to have fuel left in the tank when it shows as empty rather than running out with the gauge showing plenty left. The tank should not regularly be run low when there is an in-tank pump as the fuel is essential to keep the motor running cool to prolong its life.

[agentdagnamit]

Agreed, but more accurate would be even better! Not really asking much.