discovery 3 tdv6

anyone here had issiuses starting there d3 after a flat battery or injector change
reason is mine was only running on 5 clyinders with eccess whitey blue smoke , as it was left till I located new injectors ,, I jumped the battery as it was flat , it started very missy and steady just died , so charged battery over night , and now as it cranks , its like on the verge of starting and black smoke from the rear but will not start , plugged fault code reader in no faults showing , anyone know any ideas,or possible advise , I was looking for a possible fuel cut switch but couldn't find one tbh

Found part of the fault .i remove the alti terminal (12vred feed) and it starts fine if i replace it dosent start .so i plugged live data to notice when engine cranks ecu is reciveing 17volts .i assumed this was wrong .so i went to have the alti checked guy couldnt find a fault.(i was sure it was the fault .so guy said take a new one to try ..after fitting the new one same issuise is still there...(grrr) so refitted old one .i can only think ecu is damaged anyone hve any further ideas

Where did you get a new one? They are on back order from Denso/LR until early March.

And spurious aftermarket ones have been known to cause similar issues

ots a on going with the d3 tbh nearly a year ago now.when is were these parts were replaced..any companies that can problery check for camshaft movement

today removed head again .double checked height and bore .defo ...no problems marks or scores.
so i made a compression tester evern thow i know rear back clyinder showed buggar all.
firsty i removed camshafts and 2 rockers from the exhaust bank . retested compression gauge shot up.i then replaced
the rockers and i get 0 compression .i thought wounder if the cam lobs are faulty .i then did the same removing 2 inlet rockers but i get compression .
all valves and lifters were replaced and relied of oil and timing checked .i can only think exhaust cam is possibly faulty