[spool twice]

I figured I'll post my saga with my 2a87, 3100 codes but I added 2A82 to assist those who use the search function to find this thread.

When I first purchase my car (used), I had driven home and I get a yellow half engine light (limp mode, code 3100) and I could feel a loss of power. This would cure itself after each restart. It become more and more pronounced when I packed on another 5,000miles, more so after a WOT run. Then after picking up my JB4, it would go to limp mode after every WOT run which got really annoying.

But with the JB4, I was able to read my codes accurately and got 2A87 and 3100. No biggies knowing that both the intake and exhaust VANOS solenoids share the same part # per using the search function, I decided to swap them around to see if the code would move. Cleared the code and went for another WOT run. Nope, code was still on the exhaust side. Ok, my brothers car was sitting right next to mine, so we agreed to swap solenoids to see if that will cure my 2A87, nope. In fact, his car never triggered any VANOS codes at all. At this point, I read some more up on it and I was thinking this was going to cost me $$ because I read that if the VANOS codes dont' clear, you'll have to replace that cam guide directly underneath the valve cover because it gets clogged.

Days went buy, now the limp modes were becoming more persistent even at light throttle or cruising. I came upon an idea that maybe the dealer I bought it from:

1) never changed the oil but reset the maintenance light

2) they put the wrong oil weight and put in any brand synthetic 5w30 that wasn't BMW LL-01 or above approved

I decided to clean my interior and I happen to see an oil change sticker (one of those window stickers to remind you of when the next oil change in due). It was from a Valvoline oil change chain that just said 5W30 and was changed 2 days before I bought my car. No notations of synthetic, but knowing that Valvoline does not make a 5W30 in LL-01 spec, I knew that my car did NOT have the correct oil.

I ran over the Advance Auto Parts, thankfully they had a sale on Mobil 1 oil 5QTs for $32.99 with a M1 filter. They dont' make an M1 filter for our cars, so I just bought any generic M1 filter to get the $32.99 special. Bought 7 QTS of oil + filter and ran a couple WOT throttles, enough to get my oil temp above the normal 220-230 range (IIRC it went up to 250). Two weeks into my oil change, NO CEL or error messages.

Moral of the story, If the oil is either:

1) old
2) not the correct weight
3) not BMW LL approved

that this can cause a frustrating stuck VANOS "over retarded" codes.

Glad I didn't fork over $$ to change the cam guides Hopefully this will help others who have VANOS codes issue's

[J3NGOe90]

Same thinng happened to me after changing oil no more vanos codes or limp mode, but my oil was dirty

[rtgirard]

Good info! Thanks for sharing.

[E36graduate]

I bet your code has come back since you posted?

[spool twice]

No actually

[Meeni]

Wrong oil weight can do that. The vanos solenoids are oil operated, if the oil is not thick enough, it will not build pressure as intended. (btw the chain tensionners are also under oil pressure, just think what could happen if they skip... ).

[chronos6]

Originally Posted by Meeni

Wrong oil weight can do that. The vanos solenoids are oil operated, if the oil is not thick enough, it will not build pressure as intended. (btw the chain tensionners are also under oil pressure, just think what could happen if they skip... ).

Wow, interesting how this motor works. Good info right in this post. Thank you for that.

I remember when I first got the car in October. Week after I decided to go to the bmw dealer and pick up oil and filter for a change. When I dranged the oil that was in it, holy shit was it black. It was just as bad as liquid tar. Gonna be replacing it every 5k miles for peace of mind.