Right, here goes...I have a 2005 X5 4.8 iS,the  key fob stopped working but can lock the doors manually. A few days ago the car felt like fuel starvation then it picked up again.

 Went to work, parked the car up for 9 hours, then after work, came to start it up and it just did several  long cranks and wouldnt start. Put a tester on the pump wiring and there appears to be power going to the pump, but when you turn the engine over theres no sound from the pump but the car sounded like it wanted to start. Would the battery being flat in the remote key fob prevent the car from starting? I have bought a pump relay in case its that but would like to know  where on the vehicle this is located? The car battery keeps going flat so dont know if the battery is kaput now. The vehicle is fitted with an LPG doughnut tank at the back with the battery underneath this, which could be a pain if its the battery thats the problem! Also fitted with a stainless steel after market exhaust system. Any ideas, information or advice would be very gratefully received!

Thanks, J

Hi Jerry

I would definitely start with checking the battery with a heavy duty discharge tester and if it's no good then replace it

Let us know how you get on with it.

Hi, may sound silly but have you checked the fuel filter? I had problems starting and this was down to dirty fuel filter. Changed and no more issues. 😉