autocom will read nearly every car on the road its garage level and cheap as chips compared to the garage gear,
so would appear yours are 4 degrees a drift, the question i would have is that due to low oil pressure problem,, rarely have seen very drty ol or cheap oil filter cause issue with vanos timing ie anything that effects the oil pressure to the vanos will effect how they work ie its oil pressure that forces them to rotate to alter the cam to crank and cam to cam timing vie the ecu controlling it in split seconds depending on the load on of load off of the engine throttle as such.. so would be a good idea to start form a known good spot ie good oil and good filter, also there is no middle ground with the prince engines when it comes to timing chain as every thing depends on knowing this is correct,, put it this way every time i get one in front of me my first question to anyone when was timing chain done last if car has done over 60.000 miles then its a must do job before much else,, as a old chain will cause lean running and can cause rich running will cause 02 sensors and cat issue will cause pcv system plausibility faults and on most doing a complete kit and must include the bottom sprocket as these dont last past 60k as feather off the teeth and widen the teeth dips and you can rotate the crank within the dips and that will easy be 2-4 degrees of timing that moves around depending on throttle on or off, also the chain stretch and poor after market chain tensioners ie i always these days at least fit a genuine chain tensioner as they are so much better and longer,, ie latest spec N18 and B series bmw chain tensioners are the best and fit, £53 from oceam bmw plymouth, ocean also do latest chain set ie guides bottom sprocket and chain and bolts around £200,, truscots ie the thp engine is same engine as mini sometimes they are cheaper for some parts..
even compression tests can be altered my a engine with to much over lap from chain stretched etc.