[nicked8]

TLDR: Trying to understand differences in VANOS (camshaft) adjuster units 11367522290 and 11367583208 as I try to resolve a 2A99 code.

I have a 2006 E90 330i with about 126k miles and have been chasing some VANOS codes. Initially I was getting 2A82, 2A98, 2A99 and similar codes that seemed to switch from intake to exhaust when I swapped VANOS solenoids. After cleaning the solenoids didn't help, I replaced them both with Pierburg units from FCP Euro. This seemed to resolve the issue and I drove for a few months without any new codes.

Then a few weeks ago I scanned the car and 2A99 had reappeared. At no point have these codes ever triggered a check engine light - I've always seen them when scanning the car on my own. I cleared the 2A99 and drove the car about 500 miles to see what would happen. I scanned the car again and this time 2A87 had appeared - the first time I've seen this code.

So at this point I'm thinking I'm dealing with the broken VANOS adjuster unit bolts that have been subject to recall or a potentially cam ledge bearing wear. I decide to pull the valve cover and order a new gasket, eccentric shaft sensor (I had oil in my connector), and a bunch of the updated VANOS bolts with the plan to replace the security torx ones that are known to back out and break.

Well I should have done some more research ahead of time because I pulled off the valve cover yesterday and my VANOS adjusters are different - they don't have the rearward security torx bolts. My unit has a black cover on the back side (camshaft side) and no bolts - instead it has bolts on the front side (facing away from the engine). I go onto realoem and realize that my units must be 11367522290 which was used 09/01/2004 — 05/20/2009 and was superseded by 11367583208 from 02/02/2009. My N52 is a 07/2005 build so clearly has the earlier unit.

My question is - are these early units susceptible to similar issues with the bolts? All the front facing bolts look fine to me - all are present and none seem backed out. If I eventually need to replace the units, I assume I would use the updated part number?

Separately, if these older style adjusters don’t have the same bolt problem – what else should I consider as the cause of my 2A99 code? Obviously hoping it’s not cam ledge bearing wear. I took off the front intake camshaft cap and fortunately there were no grooves worn into the cap. It has the expected light grey wear, but there’s zero lip when I run my finger over it. The inside of the engine is super clean and has clearly seen regular oil change intervals so hopefully that helps. Of course, my codes are exhaust side which I can’t examine unless I get a timing tool kit.

Curious to hear any insight on the different adjuster unit styles as well as any suggestions regarding the code.

[WheelNut2]

This sounds a LOT like my car. Also, a 2006 330i with a rough idle that wouldn't go away. I did have those same codes stored as well, but couldn't get them to come back ever. I also checked oil pressure, replaced the vanos solenoids with genuine BMW, smoke tested for vacuum leaks, cleaned the vanos filter screens (clean anyways), and ran all the diagnostics that I could on INPA and ISTA. Nothing gave me a conclusive answer to the vanos adjusters being the issue, but they were the only thing left to replace.

I also had the same Vanos adjusters with the bolts on the front and no visible signs of trouble. I just replaced them last week along with the eccentric shaft sensor and a few seals. The car runs great now. I used Febi Bilstein parts from FCP Euro Febi PN178386 (BMW PN 11367583207) and Febi PN 178385 (BMW PN 11367583208). When you goto the new adjusters you also need the new timing discs (I used URO 11367578877). The old timing discs have a different offset and can't be used with the new style Vanos adjuster units.

I wouldn't worry about the cam ledge. From what I've read if you don't have a groove then you are all good. It also seems more prevalent on newer N52s? But that is my speculation.

[nicked8]

Originally Posted by WheelNut2

This sounds a LOT like my car. Also, a 2006 330i with a rough idle that wouldn't go away. I did have those same codes stored as well, but couldn't get them to come back ever. I also checked oil pressure, replaced the vanos solenoids with genuine BMW, smoke tested for vacuum leaks, cleaned the vanos filter screens (clean anyways), and ran all the diagnostics that I could on INPA and ISTA. Nothing gave me a conclusive answer to the vanos adjusters being the issue, but they were the only thing left to replace.

I also had the same Vanos adjusters with the bolts on the front and no visible signs of trouble. I just replaced them last week along with the eccentric shaft sensor and a few seals. The car runs great now. I used Febi Bilstein parts from FCP Euro Febi PN178386 (BMW PN 11367583207) and Febi PN 178385 (BMW PN 11367583208). When you goto the new adjusters you also need the new timing discs (I used URO 11367578877). The old timing discs have a different offset and can't be used with the new style Vanos adjuster units.

I wouldn't worry about the cam ledge. From what I've read if you don't have a groove then you are all good. It also seems more prevalent on newer N52s? But that is my speculation.

Thanks for the reply! I had actually seen your thread and found it very informative so thank you for documenting for others like myself to learn.

At this point I’ve pretty much drawn the conclusion that the early VANOS adjusters we both have don’t seem to be susceptible to the broken bolt issue. The most recent recall applies to the newer models that are aligned pretty closely with the date realism lists for the start of the updated part number. Also our older ones have the different bolt setup as previously mentioned.

However, it’s definitely interesting to hear that replacing the adjusters was potentially the solution to your issue. I’m debating replacing them while I have everything opened up but somewhat hesitant to drop another $500 in adjusters plus more for a timing kit and various one time use bolts without knowing for sure. I thinking I may button things up as they are, see if the new eccentric shaft sensor makes a difference (although I don’t have my hopes up too high) and continuing to monitor codes. It makes me feel much better having been able to check the intake cam cap for grooves and finding nothing. Now the exhaust side could be a different story, but checking that brings me back to needing a timing kit.

Plus I already have my hands full needing to fix a stripped valve cover bolt hole and replacing the CCV system after finding the hose that connects to the back of the VC was broken - both results from some hack who worked on the car prior to my ownership. Can’t wait to have the pleasure of taking the intake manifold off too!

[fastboatster]

did you clean vanos check valves? also, I think 2a99 is an exhaust side code, can't really tell how the exhaust ledge is based on the intake cam front cap.
Probably your vanos check valves, though. Another possibilty is your engine is out of time on the exhaust cam, can be a bad chain tensioner or a broken guide. Not too likely, though, but probably should check that the engine is in time.

[nicked8]

Originally Posted by fastboatster

did you clean vanos check valves? also, I think 2a99 is an exhaust side code, can't really tell how the exhaust ledge is based on the intake cam front cap.
Probably your vanos check valves, though. Another possibilty is your engine is out of time on the exhaust cam, can be a bad chain tensioner or a broken guide. Not too likely, though, but probably should check that the engine is in time.

VANOS check valves were removed months ago and were all good. One of the good things about this engine is it’s definitely seen regular oil change intervals - the inside is pretty spotless.

If the engine was truely out of time, don’t you think it would be more obvious? It runs totally fine, idle is solid, never thrown a check engine light. The codes I’m seeing are only shadow codes stored in the background that I see when periodically scanning the car to check things over.

I’ve had the car for the last 8k miles so not a huge sample size but still a decent amount to put it through its paces.

[fastboatster]

Originally Posted by nicked8

VANOS check valves were removed months ago and were all good. One of the good things about this engine is it’s definitely seen regular oil change intervals - the inside is pretty spotless.

If the engine was truely out of time, don’t you think it would be more obvious? It runs totally fine, idle is solid, never thrown a check engine light. The codes I’m seeing are only shadow codes stored in the background that I see when periodically scanning the car to check things over.

I’ve had the car for the last 8k miles so not a huge sample size but still a decent amount to put it through its paces.

decent idle is subjective, plus this is an inline 6 so even if the timing is slightly off, might not degrade smoothness too much. The code you got is a correlation code on the exhaust side, and it makes total sense to verify if this is static condition (timing is not quite there when engine is off) or dynamic (dme can't adjust it when running). And you haven't checked the exhaust cam ledge.
I'd start with timing check, it's not difficult to do compared to checking the exhaust ledge.

[WheelNut2]

Wait, the car runs perfectly smooth? No idle issues, no lumpy low RPM operation, no hesitation, normal power and MPG? If the car runs great I wouldn't do anything. Why chase something that isn't actually a problem?

[nicked8]

Originally Posted by WheelNut2

Wait, the car runs perfectly smooth? No idle issues, no lumpy low RPM operation, no hesitation, normal power and MPG? If the car runs great I wouldn't do anything. Why chase something that isn't actually a problem?

Yup, the car runs fine. If I really nitpick, the idle RPM moves ever so slightly more than my E92 with an N55 but you have to really stare at the needle to even see it. Driveability and responsiveness seems totally normal. No hesitation when revving from idle or at any other time.

This whole thing started because when I saw the shadow codes, my mind jumped to the VANOS actuator bolts and I thought I might have caught it early before they really started to back out and cause real problems. Obviously, since we’ve determined I have the earlier actuators, that ended up not being the case.