This has appeared on the computer in a 1987 XJ-S 3.6 (manual) The car starts and runs normally but the starting is not instantaneous.
Could this be because the battery is fragile and does not readily hold a full chrge ot is it likely to be fuel pump/filter or the fuel pressure regulator. Thje error code can be prefixed by a flashing "Fuel Fail", but not every time.
Any advice would be appreciated.

 

If the Fueling Failure codes are the same as XJ40 then FF3 is Coolant Temp Sensor.

bob

 

Thanks for this Bob I replaced the coolant temp. sensor a couple of years ago at the same time as renewing the thermostat. The parts came from David Manners but OEM or original Jaguaar I can't remember. The car has run very little until recently when it is standing in for a sick XKR100. Today the error code flashed very briefly as FF8 with the usual fuel fail message. any ideas? The fuel comsumption has fluctuated between 31mpg on a run at motorway speeds to 23mpg on shorter trips.Seems normal!.