Could be egr but I would be checking map sensor,pipework for air leaks and maf aswell as they all work in conjunction with each other.
Fuel pressure issue initially I would replace the fuel filter unless it’s been done recently and if that fault persists measure pressure from LPFP and go from there
Independent bmw specialist garage. couldn’t still put his finger precisely on the problem and suggested a 1. new air mass meter and 2. fuel pump package replacement. Didn’t have much confidence in him if he couldn’t pinpoint the exact issue. Fuel pump sounds exactly the same…
can’t afford the price he’s quoted. Which of the two remedies do you go for!!!??
It’s 65 coupe, great condition, not an issue with it starting or picking up speed (driven over 450miles over the weekend, top speeds 110-120 no problems)