My Daughter bought an e46 a couple of months ago. I already have an e60.
I had no experience and neither did my mechanic of the vvt motor. The reason i am posting is that it took me some time to get some information together. Some of the information given is incorrect.
I am fortunate enough to own a gt1. This immediately picked up two fault codes, one being the motor and the other being the sensor. But at over £400 for both we really wanted to see what was really wrong, as the chances of both going were highly unlikely.
Both eml and engine light were coming on. My theory at this stage is that a bad motor will be picked up by the sensor. And thats why you get both faults.
I eventually read a post that someone had hit the vvt motor gently with a hammer, like you did years ago with a starter motor. The first light would come on then the second light and within about seven attempts to start it would not start.
left hand cover off. And a couple of taps with the hammer. Started no problem! And the lights would go out after maybe 8 times starting the vehicle.
Ok, so we now knew it was the motor, and it would eventually fail again, although after a week it was still ok. We had bought the motor so we would change it.
It took a couple of hours and i wouldn't say it was an average diy job. Some sites say take cylinder head off. What they really mean is take rocker cover off. All the work is in taking the rocker cover off.
I would not advise doing this job unless you are very competent.
Now my most important bit of information. YOU DONT NEED TO RECALIBRATE ANYTHING ON A COMPUTER. WHEN YOU HAVE THE JOB FINISHED TURN KEY TO POSITION 2. DO NOT START CAR. WAIT FOR ABOUT A MINUTE. THE CAR WILL AUTOMATICALLY FIND THE MOTORS START STOP POSITION.
Many sites say that you have to recalibrate it on a gt1 or whatever. You can recalibrate on a computer. The gt1 clearly tells you that it should be done automatically.
As for the motor it takes 5 minutes to sit in!
I hope this helps someone in the future.