2005 LR3 V6 intermittent starting problem.

I am hoping someone can point me in a new direction as I am running out of ideas. This summer my wife had the LR3 one province away on a trip and reported that one day it did not start. But she did some more shopping and came back and it started. The next morning it would not start and I had it decked over to a shop where they started it many times over two days and it never failed to start. They reported no codes displayed.
It has happened a number of times since to me, but it will be fine for weeks or months before acting up again. The starter is fine and it turns over nicely until the starter times out. Battery is strong. I have replaced the crank sensor and the fuel pump, and I have a pressure gauge on the rail that always shows 60 psi. If I bleed off pressure it jumps up to 60 as soon as I hit the key so I am ruling out my new fuel pump and also the relay. I have a GAP tool and I have never seen a code. Tonite after weeks of no trouble I jumped in in a hurry and nothing. I cranked until it timed out twice and then took my wife's car. Two hours later it fired right up. ***. I would appreciate any suggestions as to where to go next.

My initial gut reaction is the anti theft module may not be detecting your key properly. Not sure but it seems like a reasonable possibility.

Thank you for the reply. I have somewhat ruled out the immobilizer as the key turns in the ignition and the engine turns over just fine.
I think is not an uncommon LR3 problem as I see lots of threads started questioning the same symptoms. But when people ask for help it is rarely resolved so there is no online database of corrective action.

Check this thread out very similar to your problem. Fixed with an ecu reflash.

https://www.landroversonly.com/threads/engine-immobilized-not-recognizing-key-fob.54318/

Thank you. I had not seen that thread, and perhaps I do need to look harder at the immobilizer.

I just wanted to come back and finish this conversation up, as it was frustrating to see other people on various sites with the same issue, but the threads would peter out unresolved, so I was really on my own dealing with this. Over the last 6 or 7 months I replaced the fuel pump and crank sensor, dismantled the steering column, and played with various methods of trying to rule the immobilizer in or out. These were all suggestions to me or others with the same issue. I am not 100 per cent I have solved my problem, but it has been almost two months since the last no start so I am somewhat optimistic. What I found was a bad connection in one of the cam sensors. I had not given them much consideration because nothing I read ever suggested they could be a problem without throwing a code, and that even if there was an issue it would cause a drivability issue and not a no start issue. But I found I could cause it to not start by wiggling the connection, so cleaned up the connection and adjusted the contacts with a pick and no problems since.

Can you send a pic of the connector you messed with?
**Disregard, I found them and the wires and connections are good. However it does seem like it's harder to start than it was before I cleaned the connections. Go figure...

I think I have a similar issue and would love to hear more about that cam sensor connection. I have a v6 in my case (gasoline).

My issue ended up being the fuel pump relay. I replaced it and am several months in with no issues, starts every time.