Purchased 2004 Discovery last week. Yesterday it stalled as I pulled into my driveway. Started right back up. I shut it off, went in the house, came back an hour later, cranks but no start. Poked around a little bit and it started. Drove about three miles, shut it off, a bit later it started up no problem. Drove a mile to a storage building, shut it off, twenty minutes later, cranks but won't start. Poked around for a few minutes and it started. Drove back to the shop, shut it off, won't start. Hooked up scan tool, no codes. Swapped the fuel pump relay with the ride leveling relay, no change. Checked spark, no spark then all of a sudden it had spark and started up. Still no codes, a few minutes later it stalled and no spark again. I suspect crank sensor since there is no spark and when it starts it is not rich or flooded so that tells me injectors are not firing either. Also when it stalls it just shuts right off, not like it's running out of fuel, more like you just switched it off. My other thought was the main relay but the ECM communicates with key on, check engine light is illuminated so I know the ECM is powering up. Eventually it started again, I drove towards home, made it two and a half miles, it stalled, few minutes later started up and made it another half mile to home. I ordered a crank sensor, sounds like a bugger to change. Has anyone else had this scenario? Eric at Atlantic British said it sounds like a crank sensor and it's a common failure. Vehicle has 105,000 miles on it.
Getting the two connectors aligned and connected with one hand at the end of your fingertips, and working blind because once your hand is in there you can't see anything, now that was a bitch. I had to take a time out after several attempts.