Nissan Primera P12 2.2 Dci 04 Changed timing chain

Hi all, can anybody shed some light for me.

A friends car's timing tensioner failed due to bad chain I presume and the engine suffered catastrophic failure.
Some chancers changed the head an reused the old chain.
He came to me with the car not idling and throwing p0016 and p0036.
When I found out that the chain was reused, I set about changing the primary and secondary chains as per the esm.
Now it's still acting the same, slow to start, and clunking on idle. Slightly better in that it stays running but still not idling right.
I swapped both sensors for 2nd hand ones, no change, checked all wiring to the ECM for continuity, earth leaks and positive leaks. Fixed a broken main engine earth.
The only thing about the sensors is that the read 900 ohms resistance instead of 1800-2400 as the manual states.
I doubt both are gone.
The car acted fine ONCE on a test drive after the mil came on, the only problem was the mil.
The rest if the time it's in limp mode with bad idle.

I'm at my wits end so any help is much appreciated.

Ac

Just for the benefit of others, the problem I had was that the vacuum pump sprocket on the camshaft on the x-trail head that was fitted by another garage is slightly different in design to that on the p12.

It has a ramp before the top dead centre interrupter protrusion and led to an incorrect cam pulse reading.
Funny enough this fault threw a crank related DTC.

Three weeks and the purchase of an oscilloscope later we finally got there!

Great feedback thanks

Chicaneauto wrote: Just for the benefit of others, the problem I had was that the vacuum pump sprocket on the camshaft on the x-trail head that was fitted by another garage is slightly different in design to that on the p12. It has a ramp before the top dead centre interrupter protrusion and led to an incorrect cam pulse reading. Funny enough this fault threw a crank related DTC. Three weeks and the purchase of an oscilloscope later we finally got there!