@Jhgrn3 - sorry, meant to follow up on your earlier post, but wanted to look up something and forgot to post back. I was recalling another member who replaced his coolant crossovers and such, and couldn’t get the car to start after - no codes either. Eventually towed it to the dealer. Turned out there were two plugs that can get crossed, but I couldn’t remember which and couldn’t find the thread. Just took another look and finally located it:
https://www.landroverworld.org/threads/lr4-no-start-after-coolant-pipes-replaced.41653/
It’s the engine coolant temp sensor and the manifold diverter - both on (or near) the rear crossover/heater manifold. So that’s something to check.
If it’s not that, maybe double check your MAF, MAP, both ECT sensors, and throttle connections. Check the VVT connections.
KTM’s suggestion is a good one, and something that occurred to me. Any chance you are 180 out? If you did it by the book and nothing spun while you were installing the chains, its probably not likely. Plus, no codes (according to your other thread) - I would expect a cam/crank position code if you were out of time - probably even 180 out, though not sure.
With no other codes to guide you, and assuming all your sensors are connected, the only think I can think to do would be to go back to the basics - check for spark and fuel pressure at the rail. Since you say it wants to start, I’m assuming you’re getting some spark, so I’d be leaning towards fuel. Possible injector failure? Did you disconnect the HP fuel pumps or fuel rail pressure sensors? Fuel pump fuse? Check your fuel line connections for leaks.