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I can't get my petrol tank on my XJS to properly fill up. It stops about 3/4 full and won't take any more. What could be the problem please.
Thanks
Jeff

Jeff

How do you know it's only three-quarters full? Is this based on what the gauge is telling you? If so I would say the gauge is probably misreading due to gauge/sender unit fault.
You could try earthing the "live" wire from the sender and then the gauge should read full. Thus eliminating the gauge. (Or not)

Then it may be that the float is holed and will not float on top of the fuel, or the sender electrics are u/s. In which case replace the sender unit.

If you know that the tank is not full through some other means (?) please ignore the above

DH Dove

Jeff

How do you know it's only three-quarters full? Is this based on what the gauge is telling you? If so I would say the gauge is probably misreading due to gauge/sender unit fault.
You could try earthing the "live" wire from the sender and then the gauge should read full. Thus eliminating the gauge. (Or not)

Then it may be that the float is holed and will not float on top of the fuel, or the sender electrics are u/s. In which case replace the sender unit.

If you know that the tank is not full through some other means (?) please ignore the above

DH Dove
I take it it's not full because the gauge only reads 3/4 full and it only takes about £40 to full it up from the red. I would expect the tank to hold more than that. Would this be right?
Thanks
Jeff

Have you tried putting in much less of the nozzle? It definitely helped on my old coupe.... Should be c80 ltrs i think....

hello Jeff Turbo; That sound like the fuel gauge. A full tank is £60.00+ Phil

Jeff

How do you know it's only three-quarters full? Is this based on what the gauge is telling you? If so I would say the gauge is probably misreading due to gauge/sender unit fault.
You could try earthing the "live" wire from the sender and then the gauge should read full. Thus eliminating the gauge. (Or not)

Then it may be that the float is holed and will not float on top of the fuel, or the sender electrics are u/s. In which case replace the sender unit.

If you know that the tank is not full through some other means (?) please ignore the above

DH Dove

,
I take it it's not full because the gauge only reads 3/4 full and it only takes about £40 to full it up from the red. I would expect the tank to hold more than that. Would this be right?
Thanks
Jeff



but how do you know its actually empty when on red ?? , as the gauge may be telling porkies then to..

BB

Jeff

How do you know it's only three-quarters full? Is this based on what the gauge is telling you? If so I would say the gauge is probably misreading due to gauge/sender unit fault.
You could try earthing the "live" wire from the sender and then the gauge should read full. Thus eliminating the gauge. (Or not)

Then it may be that the float is holed and will not float on top of the fuel, or the sender electrics are u/s. In which case replace the sender unit.

If you know that the tank is not full through some other means (?) please ignore the above

DH Dove

,
I take it it's not full because the gauge only reads 3/4 full and it only takes about £40 to full it up from the red. I would expect the tank to hold more than that. Would this be right?
Thanks
Jeff



but how do you know its actually empty when on red ?? , as the gauge may be telling porkies then to..

BB
I haven't run the tank dry to find out yet

hello Jeff Turbo; That sound like the fuel gauge. A full tank is £60.00+ Phil

If I run the tank dry would it affect the car in the future?

Jeff Turbo,

Why not just syphon the fuel out and then note how much you put back in and start from there in terms of working out how much it can hold?

Paul

Jeff Turbo,

Why not just syphon the fuel out and then note how much you put back in and start from there in terms of working out how much it can hold?

Paul
Thanks. I will try that in the future as i'm in no hurry at the mo.

Hi I have had problems with strange readings on my Cabriolet. It turned out the tank sender was faulty. The floats are also known to be a problem when they fill with fuel. I used a stick down the filler, to dip the tank when it said empty, this confirmed I still had gallons of fuel
Regards Kels

Hi I have had problems with strange readings on my Cabriolet. It turned out the tank sender was faulty. The floats are also known to be a problem when they fill with fuel. I used a stick down the filler, to dip the tank when it said empty, this confirmed I still had gallons of fuel
Regards Kels
If the sender is at fault, where can I find it, and how do I change it please

Thanks
Jeff

Its in the boot, Remove the spare wheel and the Battery oh and carpet . It right in the middle. you cant miss it. I have the problem, I have a full tank and it tells me it empty. The goes to full again. Its a lose wire, it could be the same for you.

Many thanks

Jeff Turbo,

Persistently low fuel gauge readings are often caused by the anti-slosh module which is located in the boot, rather than the gauge sender unit.

To eliminate whether the problem is the gauge itself, earth out the snder unit and the gauge should go straight to full. This will at least show that the gauge is capable of full movement.

Anti-slosh modeules are about £75 new, so I would try and borrow one or else source a second-hand one if that is the problem.

Paul