benpaul12 62 Report post Posted June 7, 2015 To try and sort out my slighly rough idle and 1500-2000rpm surging issues I performed a VANOS solenoid clean today. I followed this DIY: http://www.e90post.com/forums/showthread.php?t=486201 I've taken a couple of snaps to show how it was all done below. Overall this was a very easy DIY, when I removed the solenoids they were both very dirty. I used degreaser and a lot of dirty oil came out. I didn't remove the engine cover, all I took out to make access easy was the snorkel that leads to the air filters. Putting them back in, I swapped the solenoids around. Tomorrow's commute will see if this DIY has made a difference to the idle and surging. Hoping to see some improvement to performance and fuel economy too. If there isn't a difference I will replace the parts with new ones, if not will go from there with scanning etc. The first shot is the front of the engine with the solenoids removed. The final two shots show how clean they were after I did it. Quote Share this post Link to post Share on other sites
str8_6 275 Report post Posted June 7, 2015 (edited) On my N52, I kept getting the error code 2A99 (Crank Shaft - Outlet crank shaft, correlation). I had a rough idle when cold starting and noticed power surging while cornering uphill on winding hill roads. The other symptom I noticed was when coming to a stop from time to time, the engine felt like it was going to cut out as it changed from second to first gear. I cleaned both solenoids and noticed a slight improvement but still surging. I cleaned them both a few more times but it still wasn't 100%. I swapped them around and the car ran really badly so I realised one of them was faulty. Replaced it and now no more error codes, smooth idle and no surging. Edited June 7, 2015 by str8_6 Quote Share this post Link to post Share on other sites
benpaul12 62 Report post Posted June 7, 2015 On my N52, I kept getting the error code 2A99 (Crank Shaft - Outlet crank shaft, correlation). I had a rough idle when cold starting and noticed power surging while cornering uphill on winding hill roads. The other symptom I noticed was when coming to a stop from time to time, the engine felt like it was going to cut out as it changed from second to first gear. I cleaned both solenoids and noticed a slight improvement but still surging. I cleaned them both a few more times but it still wasn't 100%. I swapped them around and the car ran really badly so I realised one of them was faulty. Replaced it and now no more error codes, smooth idle and no surging. Thanks for posting this. While I've noticed some definite idle improvements and some slight improvements in the lower rev range, the surging is still present, it's not as bad though. So yeah improvement but not the change I was looking for. As they parts are only $70 USD for two on the net I will replace both with new ones and give that a go. Quote Share this post Link to post Share on other sites
wtbdeath 4 Report post Posted June 25, 2015 I have two spare Solenoid to give away, they were giving fault code, I heard you could clean them up and see if it fixes problem, I just didn't bother, they are free, drop me a message. Quote Share this post Link to post Share on other sites