Difficult to start when cold

If your cold start mechanism(s) always stays on, it will be difficult to start a hot engine if at all. Could be a bad sensor or defective ECU.

If it cranks normally when hot, could be that an injector is leaking enough to slightly flood engine and this is okay when cold. Could also be cold start injector is not completely shutting off when hot.

Sounds like a weak battery, or bad connections at the battery/etc. Could also be a security system issue. Without hearing the noise it is difficult to help you pinpoint it. Maybe compile some more info with specifics like when? how often? cold or hot engine? cold or hot outside? Does the engine crank slow/start normal when it does start? Do you have any non-Honda alarms/gps/tracking systems installed? If so, that's where to start. 99.9% of the time these types of probs show up with non-factory security systems installed, it's caused by the aftermarket product, or sloppy installation by vendor.

have the injectors overhauled by a professional diesel shop
indications are that they are squirting and nit atomizing as required for a cold engine

it sounds like a fuel starvation problem it is very possible theres a blocked vent in the carb. the carb will probably will need rebuilding not very difficult

If it has not generated a "check engine " light, troubleshooting will be more difficult. You have a Cold Routine for starting that is triggered by temperature. It is possible that a temperature sensor is not good and therefore the Cold Routine is not cycling.

Contact Autozone, or Advance autoparts for a scan or talk about this part that you may need.

VAG suffer greatly with a signal failure to ECU that brings the choke on when cold. Your fault is text book of this.

Follow the top radiator hose to where it meet the engine, at that point you will see a sensor, it has 4 wires and is held in by a horseshoe clip. This is the water coolant sensor, replace it and you'll be happy again :o)

hi you will find that the cold start injector is not working it is found near the throttle bodyand injects fuel to start when cold like aq choke on older cars . it may need replacing i suspect that it is either blocked or just worn out they are not expensive

The normal reason why a hot engine doesn't start is the choke. Your fancy new range rover will have a computer controlled choke that will be activiated by a temperature sensor. maybe this has failed or is disconnected
In my ancient range rover I have a manual choke but essentially the same engine. I know that if the motor is hot I can't start it with the choke on.
The way the choke works is it restricts the airflow into the engine so that there is a richer fuel / air mixture which is needed for a cold start. If the engine is hot and the choke comes on the engiine floods with petrol and there isn't enough oxygen for it too ignite in the cylinders. To start a flooded engine you have to open the choke and crank the motor without pressing the accelerator. This pumps out the petrol vapour and eventually it will fire and start. If the computer thinks it is cold because of a disconnected or faulty sensor it will put on the choke whenever you try and start and the engine will flood.
I think a vapour lock is unlikely unless you driving in extremely hot weather (above 40 degrees celsius).