I have a 1998 Discovery that started stalling. It seems to happen in summer. Car eventually stalled and wouldn't start. Have had it towed to dealership 3 times. Have changed fuel pump and pump relay. 3rd time at dealership, they kept a month. They cannot find anything mechanically wrong. Last time they got it running and said it was a "connector", but were extremely vague. It ran for a few months. Now it has been stalled in my garage for over a month. When this happens, I cannot hear the fuel pump engage. Any ideas on what this might be?

 

Start by resetting the inertia switch on the passenger firewall, press it.
Then you need to check for power at the fuel pump, if the crank position sensor fails it will not send the signal to the computer to power the fuel pump.
A chaffed wire to the fuel pump may also be the culprit.