1.6 hdi don't start

[Ferru1104]

Hi all, greetings from Italy.
Subject is a 2008 xsara Picasso 1.6 hdi, VIN VF7**************[VIN obfuscated, can be read by forum staff].
My brother in law wanted to scrap it, I says hold on, what's the matter. Symptoms: intermittent cut-outs, limp mode, sometimes no start at all.
Mechanic says high pressure fuel pump needs to be changed, quoted 800 euros for the job. My BIL takes all for granted, not willing to spend that money prefers to scrap it.
I inspect the car, signs of general neglect inside and under the hood too. Thick burned-on coke around cylinders 1-2-3, 4 is swimming in oil. Try to start it, no start. Dash indicates economy mode, battery lamp is on continuously even with fresh charged battery.
Prime it with the hand pump, fires up at once, ticks like a swiss watch. Hm.
Scoured the web for the symptoms including this forum, all fingers point to crankshaft position sensor and fuel pressure sensor. Ordered the mentioned sensors, fuel filter, air filter, gasket set for injectors. Until the parts arrived I started the car up several times just for the heck of it, each time it started ok.
Parts arrive, I get to work. Never done this on this engine, but no big issues. Changed sensors, filters. Some genius stripped the bolts on the wiring loom/fuel return holder console above the injectors, impossible to remove it, hell job but worked around it. Removed injectors (all swam in oil/gasoline), seals, cleaned up well, changed all seals, back everything, tied up well, job done.
Primed the system with hand pump, tried to start it, no start. Cranks but doesn't fire up. Eco mode, battery lamp on. Web search indicates low battery. OK, charged the battery all night, today put it back, still no start. Still Eco mode, battery lamp on. Hooked up a second battery, still no honey. Cranks but doesn't fire up. Verified all fuses, all ok. Yes, all the connections are plugged back.
My thumbs are sore from all the pumping of the priming bulb.
After all the work done this thing won't start.
Asking all the forum experts please point to the obvious ommission.

[PaulC5]

Put the old crank shaft sensor back and see if this helps.

[Ferru1104]

Hi, done that. Still the same.