I had this problem on my 1992 745 with Regina fuel system. We disconnected the plug to the cold start injector because it was flooding each and every time. I then had the fuel ecu zapped to reprogram it. There is a Volvo recall on this procedure; some dealers may be still able to do it. It requires a special black box for zapping the module. Winter starting was hell since I don’t live near the arctic circle and don’t need the extra gas flooding the engine.