Fuel needle jumps to Zero/ range drops to 27 miles

[mikelambert]

XK8 4l 2002 Convertible.
The fuel needle keeps jumping down to Zero and the range indicator tells me I have only 27 to 35 miles of fuel. Sometimes I have only just tanked up and should have-and do have- 280 to 300 miles of range.

Is this a sender problem and if so where is the sender fitted on this model?

Is it possible and easy to fit a new sender, or must the tank be removed to do this?

Is there a diagram available to show where this is fitted and how to replace?
Any help would be appreciated

[mike020150]

Hi Mike,
Your car's problem does sound like it could have a dodgy sender unit or a wiring issue. The fuel pump and sender are mounted together on the tank along with the evaporative emissions vapour vent valve. On convertibles there is a bolt-on closing plate behind the tank. However, Jaguar regards any work on the fuel pump and vent valve area as a tank out job. In view of the work involved I would be tempted to check very carefully all the likely wiring/earthing issues first before embarking on the not inconsiderable work necessary to remove the tank itself. There should be four earthing points in the boot (plus the aerial earth). Clean each of them to eliminate poor earthing as the possible source of the problem. Similarly, trace all wiring to and from the fuel tank area to check for damage. Mike.