Our 2003 BMW 3 Series is consuming a lot of oil - do you know what's going on?

We purchased (privately) a 2003 BMW 3-Series 1.8-litre petrol automatic in late 2016, with 49,000 recorded miles. It has a stamped BMW Service Record, full MoT etc.The BMW had, prior to our purchase, three previous owners. The first owned it until late 2016, with Full Service History. Second was the supplying dealer who took the BMW as part exchange. A private owner then owned it third, for approx one month, for a daily commute of 10 miles while he ordered his new car. Our extensive test drive, including full throttle through the gears, showed no indication of any performance issues. The BMW was purchased to perform primarily as a commuting transport to and from work daily, approx 20/25miles each way. After a week the oil light came on because it needed to be filled up. It now consumes about one litre of oil every three weeks. I'm not technically qualified to grasp what has brought on this problem. I took it to my local BMW dealer, who suggested changing the head gasket. However, the issue continues. I called BMW, who didn't deny that there is an ongoing oil consumption with this E46 engine. I also discussed this E46 engine problem with two very experienced Vehicle Engineers, who suggested they were aware of this problem. Their solution was for the engine to be removed, stripped, new valves fitted etc (approx £1200, plus VAT). My son and I like this BMW so, money considerations aside, have you come across this problem before? If yes, what is the practical solution to rectify this problem? This car is currently used on a daily basis as essential transport. It drives well, other than this vexatious problem.
It's 14/15 years old. I guess what has happened is that the valve stem oil seals have finally given out and this has caused the oil consumption problem. On some engines these can be replaced with the head remaining in position. On others the head has to come off, making it a much more labour intensive job.
Answered by Honest John on

Ask Honest John