Ok so quick update so far with massive fingers crossed.
Had it on the comp/code reader nd reset all the shopping list of codes,faults went for a 45 minute 2 mile drive it cutout around 20-25 times
getting really anoyed with it limped it back to the garage connected it back up again and it turns out it was the engine crank sensor.
Replaced with a genuine landrover one and also had to repair the wire connector too as the pins had came out of the plug apparently a regular fault with them according to landrover???
Replaced both and car seams to be fine all problems seam to be gone touch wood massive fingers crossed.
Well i managed to drive it for 2 hours after fitting it nd it never cut out
Heres hoping its solved it all.still a bit unsure how it first said about the overboosting though.
But its working.....
Thanks for all the replys and help