Hi pekiLR2

Thanks for the information and the link to that other post.
Wish I had seen it earlier, could have saved some money.
As the sensor is difficult to get to being under the starter motor, I decided to just purchase a new one. I didn't want to do the work twice. Tested the residence of the old one against the new one, both roughly the same. Can't remember the reading, I'll post it later.
Anyway, fitted the new sensor, no difference, still long crank before start.
When it's warm it starts without issue. Still no fault codes and I can't get it to throw the U code again.
At least I now know that the Autel can't read the engine temperature.
Problem is that SDD doesn't see the issue at all.
Therefore I am still rummaging in the dark. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.

pekiLR2,

do you know what the Autel shows for the Fuel Rail Pressure before starting ? 
Hung like Einstein, smart as a horse.

@gasman
cold starting problem sounds like glow plugs to me. did you check the relays?
take a look at following thread, throwing same code like yours, it is known LR2 issue with steering column lock.
but in the case of steering column lock it will not crank at all - https://www.freel2.com/forum/post316675.html

@shiggsy
Fuel Rail Pressure:
before starting - 240 kpa
idling (750 rpm) ~25000 kpa
2-3000 rpm - up to 50000 kpa

240 kpa for me too. Gasman was getting 0kpa. Significant ? 
Hung like Einstein, smart as a horse.

Autel shows fuel rail pressure before cranking 0. According to Alex, that would be normal.
Glow plugs would not be an issue as they are only used in temperatures of 0deg. C and below. Glow plugs were changed last year, not because they were not working but because of the age. Tested these ones not that long ago when I had the inlet manifold off to remove the swirl flaps. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.

I mentioned in an earlier post that I carried out a network integrity test using SDD and all passed.
That's the problem, poor starting when the car has been stood for some time but no related codes.  Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.

You're seeing the rail pressure come up quickly, you see the injectors pulse. Starts fine hot but not when left to cool.
If you get white smoke on the delayed initial cold start that points to over fueling. Difficult to imagine the injectors being lethargic only when cold.
By the time the injectors start , the ECU has worked out valve timing from the signals from the crankshaft and the camshaft sensors ... ha what about a 'lazy' camshaft sensor that fools the ECU into miss timing (i.e it's 180 out?) Surprised it wouldn't throw an error.
I read elsewhere that the camshaft sensor is only used during the 'calibration' phase of startup. Once running only the crankshaft sensor provides the required inputs as the ECO has worked out the relationship between the crankshaft and the camshaft. So faulty camshaft sensor won't be looked at for long , so changes wouldn't be caught as a sensor error?

Hi AndyP

I have changed the camshaft sensor twice and the crankshaft sensor three times as its not unusual to get a faulty new one.

As you say fuel pressure is there within one second and the first injector is pulsed within two seconds. You are also correct about the white smoke at start up, mostly but not always.

I might have to look again at cam and crank sensors again. I'll try and test them against the ones I removed. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.

You don't say whether you have to go through two start cycles , or whether it manages to start before timing out?
If on the first cycle , then you would have thought that the ECU has setup the parameters for starting.
The fact that it is consistently difficult in this cold start would point away from a wiring issue. (Though not a electrical component weakness)
You don't say how long the extended start time is?
When it does start, is a clean start , or somewhat lumpy as though some cylinders are firing but other only come in as the revs pickup?

Then there is cold .v. cold. (i.e overnight only). With the warm weather upon us has the crank time reduced?

Hi Andy
Sorry for the late reply.
The car does start on the first ignition cycle but I can't remember how long that is. It has taken two cycles a couple of times but not recently.
When it does start, there is no issue with the engine, apart from the white smoke. Once running it runs and drives normally.

I haven't used it for a couple of days as I have been busy with other work. However I needed to move it tonight and although it still had to crank a couple of times, it did start quicker.
As you say, the weather is better and warmer and appears to make a difference. What that is I still don't know. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.

My 2007 model used to be reluctant (but not as bad as yours it would seem) on cold ( < 5C overnight). I can't say which particular bit was the game changer , but a new battery and 2nd earth lead seemed moved me along (and removed all the HDC errors). Next was swirl flap removal (not on your model I think) , all new glow plugs , replacement starter motor solenoid contacts, reformed cables ends to starter motor .
My conclusion was that this all allowed the engine to crank faster and improve the compression achieved in 100,000 mile engine and get going earlier. Still white smoke on cold mornings , but definitely quicker to fire.

Perhaps, yours is one of cranking speed , with the warmer days the oil is thinner and the crank speed better to make up for a worn engine.

It is such a hassle trying to measure compression on these engines with the glow plugs buried away under the manifold, and the only way to confirm such a hypothesis.

Hi Andy
All that you have mentioned has been done already.
Battery is fairly new. Additional earth lead's to starter. Complete new starter motor. New glow plugs last year. Swirl flaps removed.
I don't have a problem with cranking speed, it's approximately 300 rpm.
Car may be coming up to 12 years old but it has done less than 60k miles.
Most of the miles traveled have been long runs. I don't use the car for short stop-start runs, we have a Renault Clio diesel for that.
Therefore engine wear and lack of compression are unlikely to be an issue.
Going to have to find time next week to have another look at it, just been so busy lately. Now at the point when I learn something new something old is lost out the other side !
Now retired so it doesn't matter anymore.
Freelander now gone.