Hi , so i recently purchased myself a 2004 318 CI ES beautiful condition with low mileage the only problem i could see with the car was the check engine light. I didn't have chance to check codes before i purchased but the car was a bargain so i took a gamble that it wasn't too serious as it drove great. I'm not new to DIY car repair i've always diagnosed and repaired my own cars where possible but when i have tried to research these codes i have struggled to find any potential causes so i thought id see if anyone here can shed any light.
The codes stored are
U0030 - vehicle area network VAN data bus A open circuit
U1050 - SCP invalid or missing data for brakes
U0139 - Lost Communication with Suspension Control Module B#
U1040 - Data Bus: body control module 8CM- no communication
U101B - Lost Communication With GSM – Multiple Bus
so all these codes sound to me like they are down to some sort of faulty control module or maybe wiring? i initially cleared the codes and they stayed clear for a couple of days but then all codes came back at once so i have left them be since. I really dont know where to start with this and would appreciate any input from you kind folk .
EDIT: Scanned car with inpa codes are s follows
2A61 - DME: valvetronic, adaptation 1
2A67 - DME valvtronic Internal fault
2C9C - DME: oxygen sensor heator before cat.1
2D0F - DME: Hot fim air mass-sensor signal
2C6D - DME: oxygen sesnor behind cat.1 aging
2C71 - DME: oxygen sesnor behind cat. 1
Right so it looks like i need myself a new valvetronic motor , replaceement rocker cover gasket to fix that slight leak and also a new O2 sesnor. anyine got any advise on how difficult it is to replace that motor for the average DIY mechanic?
DME: Valvetronic, adaptation 1