Probably just the accumulator (sphere). Try that first. Pumps tend to be very reliable. The pressure switch would be the next port of call. Sphere first. I think Mark found some cheaper OEM ones somewhere.

I have no undertray on mine. Shouldn't matter as I have had water over the block when wading and no issues. Mind you, Tomcat fried his with a hosepipe. Guess you could always unplug it and try a hairdryer.

It will run on defaults taken from the crank sensor. The needle sensor is only used for the actual point of injection and fine-tuning this by advancing or retarding the point of injection using the solenoid in the top of the pump.

R38 was fitted to some P38 4.0 and to the diesels. Not sure if that helps. I don't think there is any evidence the 4.6 was worse for slipping liners than the 4.0 in the P38. Should be the same, although some say the better blocks were held for 4.6 so should actually be less likely in those.

Put a notice under the rear wiper saying "Save Me!"

Remember to wash off the rads after wading. The mud cakes them and turns to ceramic. Same with the block.

Pretty sure one of mine went and the pedal was rock-hard. Maybe it depends how full the sphere is with fluid?

Mainly short journeys? Grill in top of cam-cover all cleaned out and the filter on the side?

Possibly. The tyres have to be able to take the weight of the L322 or they might wear the outer edges. Crap tyres might not take the weight without more air.

That's a valid point. Forgot the accumulator. That would make it hard to press!

If you do wade then check the depth first. Don't go above the wheel-arches as the intake is in the arch and it'll suck up water. The v8 has some capability to catch the odd bit that gets through but the diesel doesn't.

As others have said, it could be a sensor. Check they're all banged in all the way on the hubs. There are 2 switches in the brake switch unit. Might be worth checking as they should be mutually exclusive, that is one goes on as the other goes off and vice-versa. You reset the switch by popping...

Beat me to it.

You can get a whole hub for about £200, or could. Place in Birmingham used to do them with a Timken bearing - search MrGorsky posts. I suspect it is more likely the ball-joints than the bearing or hub though.

There were a couple of sizes used. I used a stretchy one on mine but slightly shorter and that worked.

Doubt it would have warmed that much. I'd check PaulsP38A website. Could be the tips of the solendoids aren't sealing properly or one of the NRVs is leaking. It certainly shouldn't raise itself when off!

Definitely. Once you have them the car realises the game's up and you'll never need them!

Thread here: https://www.landyzone.co.uk/land-rover/what-did-you-do-with-your-range-rover-today.202974/page-441#post-4118072

Cannot recall but pretty sure I posted it sometime. Mine have been on there years now. I cannot even recall when I put them on!

No idea if it even has one but that's how I would design it. Diag should show if you're lucky. Hopefully someone more knowledgeable will be along shortly.