Lookin for some VANOS help

[ryansbmw]

I’m looking for some help with my VANOS system.

A while ago, I started this thread about a rough/stumbling idle and stalling I was getting during cold starts.

https://www.xbimmers.com/forums/show....php?t=1751478

Long story short, initially no codes were present until eventually I got one related to VANOS on the intake side. Strangely enough, the rough idle seemed to be getting better over the course of a few weeks on its own but I would still grow a code “2D5A- VANOS intake: control fault, camshaft stuck” on cold days. It would pop up a few minutes after the car would start and then go away within 10min of driving.

Last week I took the car to the shop and they pulled both solenoids, cleaned them and swapped positions. I thought everything was fine after that. Idle was perfect, no codes, even on the cold days.

Until yesterday. Engine light popped up and actually stayed on for an hour of driving before going away, read the codes and 2D5A was there again. I was hoping it would have at least switched to the exhaust side which would indicate a bad solenoid but I’m not that lucky it seems.

I’ve been digging thru all sorts of VANOS threads and can’t really find any help on this one. For most people, new solenoids fixes the problems. On earlier N55, there was a bolt recall because the bolts holding the VANOS gear or adjustment piece would shear off. My car isn’t part of that recall and I don’t think it’s part of the 10 year extended warranty BMW offered either. (My symptoms don’t quite match either). Any ideas what it may be? Could a failing camshaft position sensor be the culprit? Or would I be getting other codes for that? Shop thinks it may be the VANOS unit itself but I can’t find any information on any of the forums about replacing that. I’m assuming that’s pricey...

[ryansbmw]

Since clearing the 2D5A code, it has not come back. Still get the rough idle on cold starts during cold days. Now that the temp has been warming up, things seem to be running fine. Maybe a little hard shift when 1st starting out but otherwise normal.

So the problem only arises on cold starts in cold weather. Any ideas what it can be? Can the cold temps mess with the fuel injector seals? And that’s causing the rough idling and stalling? Anyone walnut blast their N55? Maybe carbon build up on the valves and cold temps are the cause of the problem?

[Poppyboy]

It’s possibly the eccentric shaft (Valvetronic), sensor or motor. What’s the year, model and mileage of your X5?

[ryansbmw]

2013. X5 35i, N55 motor. 120k miles.

I’ve read a few posts saying this was the culprit but in all cases I have read, there was a specific code pointing towards it. It also seemed to occur on cold starts in cold and warm weather. Mine seems isolated to cold starts in cold weather. Threads on failing fuel injectors may line up with what I’m seeing. Might need to head back to the shop and have them take a look or run some tests on them.

[TwinSnailz]

Had that happen once in my x3 n55. Changed the vanos solenoid and it went away.
Usually happens on cold start. Swapping out the solenoid is super easy on the n55. Just get oem solenoid ONLY !

[ryansbmw]

Originally Posted by TwinSnailz

Had that happen once in my x3 n55. Changed the vanos solenoid and it went away.
Usually happens on cold start. Swapping out the solenoid is super easy on the n55. Just get oem solenoid ONLY !

The first few times the VANOS codes popped up, they pointed to intake side. I had the shop clean and swap the intake and exhaust solenoid positions. The only time a code popped up since, has again, pointed to the intake side. So I don’t think it’s a solenoid problem, unless both happen to be on their way out.