[pnwbmwrepair]

Hi everybody! First post here, looking for some advice as I'm unfamiliar with BMW cars. Sorry for the long text, just trying to provide info I think is relevant

This is for my girlfriends car, it's the n20 engine on a 2013 BMW x3 with 110k miles. The problem is a drivetrain malfunction, it happened last week, went away after cleaning oil out of vacuum reservoir, and came back. I got a Bimmerlink and a Bluetooth OBD reader and it has a few errors but most look unrelated except for the two in the DME.

Error codes 130f20 and 120408, exhaust camshaft and boost pressure control respectively

From what I've seen those are most commonly timing issues, but she had the timing repaired under warranty at a dealership 30k miles ago. I have the invoice and it lists chain, chain guide, tensioner, sprocket, vanos central valve, and various hoses and bolts. I'm going to call tomorrow to make sure they replaced the intake and exhaust vanos gears as I've read not replacing those can cause the new chain to stretch, but for now I'm assuming they replaced them.

Any advice on what else could cause these codes? I'm going to try changing the exhaust cam position sensor since maybe it's faulty, but I don't really want to shotgun parts at it if I'm way off.

Another side note, when I took the engine cover off to look at it, there was a bunch of oil that came out of the vacuum reservoir. Emptying that oil out seemed to stop the engine code for a week. Looking it up, that seems to be a failed vacuum pump seal, can anybody confirm if that could cause the boost pressure control error? Could that or a faulty camshaft sensor cause both errors?

Also please let me know if I should stop driving immediately, car still runs and sounds good and no error while sitting, but haven't taken it for a test drive since the error came back

Thanks for any help! Happy to answer questions