Your help appreciated

2011 diesel 2.4 cdi, 200K kilometers just passed.
I have an intermittent engine issue. Symptoms are: occasionally the engine ‘hiccups’. Like a cylinder does not fire. Occasionally it stalls when idling. Occasionally the power as excepted from the turbo an around 2000rpm does not appear, the engine continues to pull but the power is missing. On one occasion this continued for some 250 kilometers. I stopped, switched off, restarted, and the problem continued. On other occasions, I switched off, restarted, and the power was back. For some time I have also had a problem with the abs in which I have the slip light on, the abs warning on, 4WD light on etc and ABS is not operative. Diagnostics show for engine P1211, P1212, P1274, U1000, P0340 on engine. Diagnostics on ABS are that the dignostic, Nissan dealer, does not detect ABS, ie it does not recognise that ABS is there.
Am not sure if I have one or two issues here. For now my focus is on the engine performance, but maybe they are related.
I have cleaned the EGR, cleaned the MAF sensor, replaced the crankshaft sensor, new fuel filter.
So, you geniuses out there … what can i do to figure out what the issue is? Nissan dealer says it’s fuel related and I need new fuel pumps and injectors etc. 4000Euro etc. I want to be more certain that it’s this before I spend of course.
Any ideas?
Thanks in advance to you all
Rob Frustrated:-)