Just purchased a second hand bmw 540 e39, 200 model.

When i went to register the car, testers told me it was running on high CO emissions. Took it to a BMW workshop (apparently this place is the next best thing to the dealer). The problems I mentioned to them were the following:
1. The CO emissions.
2. Idling; The engine would just go off when idle.
3. While driving the car at a constant speed the RPM kept hunting i.e. the RPM would go up and then down again.
4. DSC, hand brake and air bag lights were on.
5. Car was parked for a long time, so engine oil was dirty and needed flushing.
6. Slight knocking sound (like tappets)

Sent the car in and they did the computer test and found it had a couple of problems with it; solution:

1. Change air flow meter.

2. Change sensors.


They ran another test and it showed that one Vanos solenoid needs changing.

So we changed the solenoid, air flow meter and sensors (this is after 2.5 weeks of waiting for the car!) Flushed engine and changed oil (synthetic high performance)

Got the car and now it is running so rich that you could suffocate standing near the car out in the open....The car still has that hunting and it is more than before. The DSC/handbrake/airbag lights are still on and they said that it needs one more day to sort out the problems…probably a faulty wiring. I noticed now that when I accelerate hard, there is an engine belt slip sound for a split second when the car changes gear. The engine knocking is louder now. Am I being taken for a ride here? They said all these issues would be sorted out once the changes were done but this isn't the case.