2007 2.0d c30 Engine cutting out randomly

[JackCreagh]

Hi, have a Volvo c30 2.0d from 2007, currently at about 179k. Since I’ve had it the car has consistently caused issues. First issue was the car going into limp mode with immobiliser and brake failure coming up. This was solved by reinstalling the cem which we believe may have had a loose connection due to vibration.
That was sorted for a while before the car started stuttering as I drove, usually while on the motorway which was always fun. This we believed to be some sort of fuel starvation, which was the same answer we got from a Volvo specialist garage. The fuel filter was replaced and thus sorted the issue for a week or two but now less than 500 miles after the filter was it’s happening again.
Same as before the car is stuttering as it goes, it will lose all power, lights will go off everything off for a few seconds before firing back into life. Sometimes though it won’t come back on but this isn’t as common.
At the minute it’s giving 3 codes; p1412 egr pressure signal too low, p0490 egr A control circuit high, p101 maf. I have removed the egr and the egr pipe leading to the intake manifold which were both very dirty with a lot of sooty carbon build up. The egr sounded like it had loose change in it when I removed it, and when I removed it the mechanism inside fell apart so I have ordered a new one. The maf I have taken out and given a dust off with air but need to give it a proper clean with maf cleaner.

Could these be the cause of my issues or is there a chance it could still be the fuel system, my guess is injectors but I’m not sure. I also read that if installing new injectors they need mapped into the car? Is this the case? Is there anything else I can do or check in the process of waiting for the new egr, before I let a professional take over?

Thanks in advance for any help anyone can provide.