Suddenly lost all power for just a moment, then engine recovered and has seemed fine
 

After a couple hours of pushing the thing hard and fast up and down desert highways in the southern utah heat. Averaging about 70-90 and it was probably about 95 outside when suddenly gas pedal goes limp, spedometer drops to zero, flutters, then all seems normal again. There was a check engine light on when I bought it 3k miles ago, code says its a cam shaft sensor, which I haven't replaced yet. Vehicle is a 97 disco with 158k miles. Thanks for any help. I live in the middle of nowhere and don't have access to a mechanic.

Also, nowhere in the manual or under the hood could I find a clue as to what kind of oil this beast likes.

Another sensor has decided to attack your wallet. The Vehicle Speed Sensor is mounted on transfer case, and reports how fast you are going. If you approach take off velocity, about 114 mph, it begins to cut injectors and spark to return vehicle to safe speed. When they go bad, they can do this at normal driving speeds. There is a rebuild article in out tech section.

You can unplug it and drive, won't have speedo or cruise.

There is another sensor that can kill spark, it is the crank position sensor. It normally shows up as can't restart until engine cools down, so this may not involve it.

The beast likes 15W40 Rotella. In the manual there is a section on viscosity vs temp, and above 95F things that end in W40 are advised. 30 is just too light.

Hot weather oil 10/40 to 20/50, real cold weather 5/30.
You have to replace the cam sensor or the ecu can't maintain a proper timing for the enge and it is not what is causing this problem.
As for the current issue, possible crank position sensor starting to fail.

Thanks guys, yea I am planning on replacing the cam sensor, I just got the thing about a month ago. Vehicle speed sensor sounds interesting, it actually cut out when I was only going about 75, although I had been pushing it a lot faster than that not long before. If that sensor were failing, would it make sense that it had done so only once, and only shut the power off for about 2 seconds?

Also, can anyone recommend a good place to buy the camshaft sensor online? I have heard they are pretty easy to replace yourself, even with the downright shameful lack of mechanical knowledge that I admit to having.

Atlantic British