[330istocknot]

330I 2006, E90 140K MILES AUTOMATIC, these codes showed up 2 months after i purchased the vehicle.

2AAC - Variable Intake System 2 - This code means, you small disa valve inside the manifold.

Symptoms:

-Bouncy RPMs
-Hesitation on acceleration
-RPM would bounce when at a stop light, as if the fuel was running out.
-Uphill car would hesitate and act as if it was running out of fuel.
Shadow code on DME 2AAC.


Located here:


For this process, you need to remove your intake manifold to access this part. (Youtube a tutorial to find how to remove the intake manifold.)

After i removed it, i found that my Disa valve was stuck half way open, which would cause the car to throw code 2AAC.

here is a picture of it.

After replacing this part, the code disappearted and my MPG went from 188 to 20.1MPG.

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2AA9 Variable Intake System conversion 2 - Vanos related.
2A87


Symptoms:

Shadow code 2AA9

I believe this was triggered by the faulty Inner Disa, 2AAC, so i would tackle the DISA first, then clear codes, and see if this code comes back.

However, i had spare Vanos from my last vehicle, so i replaced them. Some suggest to clean them before replacing them. (Youtube how to clean vanos for tutorial.)




After replacing VANOS, code was gone.

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2E98 - Alternator communication - Due to aftermarket or Alternator not correct AMPs.

Symtoms:

2E98 on DME.

My original alternator for my 330i 2006 was a 180A alternator, i went full retarded and bought an aftermarket 150A alternator.

You will be surprised to find out, the 150A was strong enough to run the car as normal. AC worked fine, car works as it should, Navigation as well.

In other words, if you need to run a smaller Alternator as an EMERGENCY until you get the right one, you can. BUT I DO NOT RECOMMEND IT. I only used it for 30 days, i can't really tell you what can happen after running the lower AMP alt.

Here is the size difference of each alternator, as you can see by the size, the 180A on right and smaller 150A on left


After replacing with the correct 180A alternator, the code 298E disappeared.

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29D2 - Combustion Misfire - Cylinder #6


This means there is a misfire on cylinder 6, the quickest way to find out if it is an ignition coil, which is the most common thing, you need to swap coil #6, with another coil, in my case i did coil #3. Clear codes, then turn on the vehicle, if the error moves to coil cyl #3, that mean it is the ignition coil.

In this case that was the reason, as soon as i pulled #6 out, i found this..




Not sure how that happened, i replaced the coil and it fixed the misfire.


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I thought it would report my progress, it may help some in the future, as i did not find much information about the 2AAC error, i said, why not just report all the progress.


Now, my last codes i need to fix, are the

29F4
29F5

both of these have to do with catalytic converter... once i find the answer i will update you all.

Hope this helps some now and in the future!

[Ian mead]

Nice job well done I’m getting a intermittent vanos code so need to clean mine

[zboost]

For those:
29F4
29F5

How is your oil consumption? If the engine burns oil it usually triggers those, sometimes you might even get CEL on. You can drive safely though.

[330istocknot]

Originally Posted by zboost

For those:
29F4
29F5

How is your oil consumption? If the engine burns oil it usually triggers those, sometimes you might even get CEL on. You can drive safely though.

Actually now that you point it out, it does burn a lot of oil, AND i just got the check engine due to these codes. Hhmm, tell me more about what you know about this. Is it the actually catalytic converter, or maybe a sensor down there?

You were on point with this.

[zboost]

Originally Posted by 330istocknot

Actually now that you point it out, it does burn a lot of oil, AND i just got the check engine due to these codes. Hhmm, tell me more about what you know about this. Is it the actually catalytic converter, or maybe a sensor down there?

You were on point with this.

I can tell you for sure after 3 years with N52, the culprit of the problem is excessive oil burn, which leads to cats being clogged and this is why it throws you those codes for both banks (bank 1 and bank 2), which actually stand for "catalytic efficiency below threshold".
This is not easy to fix. There are a few things that can be done to lower oil consumption. You should replace oil separator and the oil breather hose, this is a must for every N52. If this doesn't help, the consumption is left to be from the valve stem seals and piston rings.
So if you are not up for an engine rubild (expensive) you either get used to driving with the CEL on or you can consider a decat manifold or just putting an o2 sensor adaptors so you don't get a CEL on.

[wacuna]

What is the resolution for codes 29F4, 29F5? Thanks

[norulz]

very beautiful thread , many thanks !

[gabriel bevilacqua]

Hello my Name Is Gabriel. I'm from Brazil. I have the error 2aa9, even after changing the two DISA valves.... can someone help me?