[BennyD330i]

Thanks for confirming - I will def. replace the bolts.

I will take photos throughout the process and post them Sunday evening as to whether or not this fix resolved my issue.

Ben

[BennyD330i]

With the car throwing two codes indicated a faulty shaft sensor I headed to the dealership and bought the valve cover gasket kit, set of new aluminum valve cover bolts, and the eccentric shaft sensor ~$490 with BMWCCA cardholders discount.

I would be more than happy to do a DIY, step by step, tools needed, tricks, etc on this repair for anyone, just PM me.

Here is the "skinnied down" version with pics.

*Remove positive battery terminal from the battery*

I removed the engine cover, engine cover mount, left front sway bar, cabin filter assembly, and additional plastic ledge assembly to open the engine bay back to the firewall. (see attached pics)

Unclipped all electrical adapters to coils, removed 6 coils, Removed the round eccentric shaft sensor plug from the top of the valve cover (see pics), pinch and unclip the "oil vapor hose" from the back of the valve cover. Remove valvtronic motor connector.

I then removed the electrical harness that is bolted to the valve cover.

With all wires and hoses disconnected your now ready to start removing all 24 bolts from the valve cover. You will find that one of the valve cover bolts sits under the Valvetronic motor which will have to be removed in order to access the bolt. (See pics)

The valve cover will now be loose however it took alot of patience and finessing to get it completely off. It sits tight in the back left corner by the ECU and firewall.

Once off the eccentric sensor sits in from the cam shaft and is held on by three bolts. There is a through hole in the orange timing chain guide to access the lower bolt. Completely unscrew all of the three bolts to release the sensor. Do not worry about dropping the bolts once fully unthreaded as they are locked in the sensor. **TRICK - once completely unthreaded you will need to give the bolt a multiple turns to drive the thread back into the sensor assembly only to get clearance to pull it up and out**

Check the sensor for cracks, sludge, etc. check and clean the eccentric shaft sensor connector for oil. (Mine connector was clean, The sensor was slightly oily but no clear sludge nor was it compromised)

Work the threads of the new sensor halfway through to allow clearance to drop into place. Bolt on.

Put new outside and inner valve cover gaskets in place.

Put valve cover gasket back on. Take your time, it's a tight fit and pain in the @ss

Use the new aluminum bolts to secure the cover securely. Keep in mind the bolts supplied with the larger spacers are the inner valve cover bolts located near the spark plugs.

Reconnect Valvtronic Motor and secure with three torx screws.

Reconnect "oil vapor hose", electronic wire harness, all 6 coils, all 6 coil electrical connectors, eccentric shaft sensor plug, and valvtronic motor connector.

Note* With everything exposed this would be a great time to change your spark plugs if your almost due.

With all wires in place and the car together minus the cabin filter, and other plastic assemlby, re-connect the battery and start the car. Reset your codes if necessary and hopefully the issue is resolved.

This complete repair took about 6.5 hours and around 500 dollars. My honest opinion is that it is a "DIFFICULT" DIY.

Oh btw, it did not resolve my issue. Car still is missing, shakes, and service soon light is still on. Also cleaned MAF sensor thinkin maybe something got through the AFE Stage 2 ProDryS however MAF, filter, and intake are spotless and that did not resolve the issue.

Tomorrow I will be putting it back on diagnosistics; thinking bad coil, bad plug (waiting on them to arrive as all 6 are original plugs that have 92K on them and will be replaced), or bad/clogged injector.

Ill keep you guys posted....

Ben

[BennyD330i]

Besides the eccentric sensor codes, the cause of my main issue was a bad engine coil. All codes are clear and car is back on the road.

[csupernova]

thanks for showing us the process. It def. helps someone in the future.

[BennyD330i]

Absolutely, thats what this website is all about and the least I can give back given the wealth of information I have gained from it.

[yakev724]

Yep, photos much appreciated. Glad to hear you're up and running. I had to replace a coil myself when a cylinder started misfiring, but it was easy to diagnose since swapping coils to different cylinders + reading codes allowed me to find the bad coil quickly. Now thinking I should change out all of them...I think 1 or 2 may still be factory originals

I was a bit anxious to pop off the cover until I saw your photos. I'm at 111k myself. Wonder what kind of preventative maintenance can be done on our engines besides plugs + coils.

I've seen people replace water pumps as well...wish it wasn't that expensive a part.

I'm planning to clean my intake valves when I have some time. Wonder how difficult it would be to clean the injectors? I know the dealer does this and it can be a good thing to have done for high mileage engines, don't think it'll be too difficult to diy either, just not sure how to deal with the fuel. There seems to be a bleeding system similar to brake calipers...we should dig up a service bulletin for proper procedure.

[gos]

Just to contribute to this thread, reported occasional hesitation under acceleration to the dealership and took it in for a look.

Primary fault code message was "Valvetronic Eccentric Shaft Sensor Plausibility" indicating that the ECU is seeing garbage readings from the sensor. Like GenePoole and BennyD330i, the dealership will be replacing the sensor for $~1300 including labor.

The list of codes my car is throwing, all valvetronic sensor related, is:

2A31 DME: Valvetronic: Eccentric Shaft Sensor: Guide
2A32 DME: Valvetronic: Eccentric Shaft Sensor: Reference
2A33 DME: Valvetronic: Eccentric Shaft Sensor: Guide
2A34 DME: Valvetronic: Eccentric Shaft Sensor: Reference
2A35 DME: Valvetronic: Eccentric Shaft Sensor: Guide
2A36 DME: Valvetronic: Eccentric Shaft Sensor: Reference
2A37 DME: Valvetronic: Eccentric Shaft Sensor: Plausibility
2A47 DME: Valvetronic: Eccentric Shaft Sensor: Plausibility

I also have a 2006 N52 E90, though mine only has 49600 miles on it. Unfortunately out of warranty by 9 months... =/

[TommyK]

I had mine replaced 3 months ago. Cars been running great since.

[BennyD330i]

Gos, Those are all the codes and the acceleration hesistation is a key symptom. Also when my sensor was bad I was getting 25.4 MPG avg and now after the new sensor install and new plugs I am back at 30.5 avg and running very well. Did you see a mean mpg drop off?

Sucks that so much labor has to go into changing out this one sensor; $500 in parts, $800 labor.

Good Luck!

[TommyK]

Originally Posted by BennyD330i

Gos, Those are all the codes and the acceleration hesistation is a key symptom. Also when my sensor was bad I was getting 25.4 MPG avg and now after the new sensor install and new plugs I am back at 30.5 avg and running very well. Did you see a mean mpg drop off?

Sucks that so much labor has to go into changing out this one sensor; $500 in parts, $800 labor.

Good Luck!

Ya it does

People please be careful out there. Not to thread jack but i went to 2 dealerships and an indy shop and no one could give me a straight answer. From the sounds of it this is a fairly new thing to break on this model of car. It seams to be happening to 2006 models first. But just as a heads up I was beating heads with service advisors who knew nothing. I went straight to a friend of mine who is the foreman of a dealership, and he knew exactly what the problem was and had it fixed in a day.

[gos]

Originally Posted by BennyD330i

Gos, Those are all the codes and the acceleration hesistation is a key symptom. Also when my sensor was bad I was getting 25.4 MPG avg and now after the new sensor install and new plugs I am back at 30.5 avg and running very well. Did you see a mean mpg drop off?

Sucks that so much labor has to go into changing out this one sensor; $500 in parts, $800 labor.

Good Luck!

I didn't notice a significant MPG change, but the first fault recorded was only 1000 miles ago. My typical per tank is about 21.5, last few have been 20.5 or so, but my routine isn't 100% consistent.

[cgalvez22]

Thanks for the pics Benny. I just got the 2A32 and 2A47 codes as well and am wondering if they could be just a bad coil like you. I have an 06 330i with 76k. No CEL or Service lights, just a little rough during cold morning starts and reduced mpg. Did you check the coils yourself or just replace all of them?
Thanks!!

[kernhills]

I am in the process of replacing mine.. and boy is getting that valve cover off a PAIN!!!

One problem I didnt forsee is replacing the gasket in the cylinder head cover that the eccentric plug goes through and attaches to the wiring under the hood of the car. I was told by a bmw tech that this gasket is also known to leak and should be replaced at the same time. I went to realeom.com and found the part, problem Im having is that I cant press it in! I know this seems strange (to me as well) but the gasket seems to be just mm too large in diameter and has no give (must have a pretty tough inner core that doesnt allow it to flex). Any suggestions on pressing this thing in to the valve cover? Im hoping someone has some experience. THanks!!

[MrQuickR1]

Funny I came across this post.
I have been having issues on my transmission shifting behavior along with hesitation on acceleration and highway miles are around 25mpg's, which I didn't know why it was low when it should be around 30.

Anyway, when I replaced the coils and plugs. I noticed the eccentric cam sensor plug had old oil/dirt around it, I unplugged it and found oil in the connection. The pins were pretty oiled up. I am thinking this isn't good and it may cause continuity with all the of the pins.
I am wondering if I should replace the top side seal, clean out the pins and plug with electrical cleaner and see if that makes a difference.
I do not have codes, or the dealer has not found any for this sensor at least.
With oil being in the area of the pins, would it be a simple fix such as clean and replace the seal or does it seem it may be leaking from under the valve cover. Anyone with this issue?

Thanks

[stoppy]

Hi!

I have a 2006 N52 330i 95000k. I have noticed that my idle is a bit low. Typically hangs out around 600rpm when just sitting at a stop light. If I depress the clutch, it bumps to around 800ish. Can see here:

http://www.youtube.com/watch?v=Zjfa3JjtyrY

I have been reading this thread because my codes after scanning the car are:
2A31 Valvetronic, eccentric shaft sensor, guide sensor
2A47 Valvetronic, eccentric shaft sensor plausibility

I checked out the plug for this sensor and like many before on this post I discovered it was pretty oily in there. I cleaned up the oil and re-plugged in but problem of the poor idle still exists. I have only owned this car for 7 months and this is my first winter. Typically I would say car idles around 850 900 when just sitting at a light however 600 to me seems low.
I have my VANOS solenoids replaces at Maranello BMW around 70,000k. No strange grinding noise or anything terrible coming from the car. So it leads me to believe its a sensor somewhere...

1) Is this normal for other 330i owners out there?
2) I haven't noticed 'sluggish acceleration' but its hard to judge. I am still thinking about replacing this sensor anyway as it seems some people note that drive ability increases once this job is done.

Thanks for the help!
Mike

[e90pilot]

Very common for high mileage N52s. Especially '06 model year. Replace it soon. It will only get worse. The sensor is kinda pricy but it will cost a lot more if you wait.

[Volasko]

Originally Posted by stoppy

Hi!

I have a 2006 N52 330i 95000k. I have noticed that my idle is a bit low. Typically hangs out around 600rpm when just sitting at a stop light. If I depress the clutch, it bumps to around 800ish. Can see here:

http://www.youtube.com/watch?v=Zjfa3JjtyrY

I have been reading this thread because my codes after scanning the car are:
2A31 Valvetronic, eccentric shaft sensor, guide sensor
2A47 Valvetronic, eccentric shaft sensor plausibility

I checked out the plug for this sensor and like many before on this post I discovered it was pretty oily in there. I cleaned up the oil and re-plugged in but problem of the poor idle still exists. I have only owned this car for 7 months and this is my first winter. Typically I would say car idles around 850 900 when just sitting at a light however 600 to me seems low.
I have my VANOS solenoids replaces at Maranello BMW around 70,000k. No strange grinding noise or anything terrible coming from the car. So it leads me to believe its a sensor somewhere...

1) Is this normal for other 330i owners out there?
2) I haven't noticed 'sluggish acceleration' but its hard to judge. I am still thinking about replacing this sensor anyway as it seems some people note that drive ability increases once this job is done.

Thanks for the help!
Mike

600 RPM is the proper idle speed after the car has warmed up!

[GoRomeo]

Yes I agree with post above. Mine, when is cold goes up to 900rpms but then about few mins after goes down to 600. You dont want to keep higher rpms as you will consume more gas. I recently cleaned and swapped my Vanos and did help to get a smoother idle. I am also planning to change my plugs in the next few days.

[stoppy]

Thanks for the feedback. As this is my first winter with this car its nice to hear this is normal. I am still going to go ahead and replace that sensor. I want to try and address the valvetronic codes. When I start it up it is a little rough.

Appreciate anymore feedback, thanks. I'll post back after sensor replacement with results.

[stoppy]

So I wanted to update everyone on my status of my problems listed earlier.

1) Idle issue is resolved. Idle is stable from starting & warmed up idle
2) Started sounds better and no shaking
3) Driving is 100% better. Smoother more aggressive shifting. Power is MUCH stronger throughout the entire rpm range.
4) No clunking at low RPM rolling starts

All in all, things are MUCH better since I started to experience problems. I would say it drives better than the day I bought it.

I followed this DIY:
http://www.e90post.com/forums/showthread.php?t=697252

This took me forever to find. Use this for torque setting:
http://www.e90post.com/forums/attach...6&d=1331856881

That DIY is for a 2007, so the 2006 is a bit different(covered with photos from a poster above) . The manual above helps with those important grey areas like:

1) Torque setting. I found when I was looking ppl have their own opinions and these are wrong. The manual is correct
2) Valvetronic motor. Manual gives you a better idea of what you're dealing with. I also found these helped:
Removal:
Disconnect the cable to the motor.
Remove the coils to the left & right of the motor.
Remove the bolt that secures the back of the motor to the valve cover.
Back out the 2 bolts that secure the front of the motor to the valve cover 2 full turns.
You will feel that there is pressure trying to push the motor out, insert a 3 mm allen wrench into the back of the motor and turn clockwise to release the pressure against the 2 bolts.
Remove the two bolts.
The motor should come out at this point, but if it does not, insert the allen wrench and turn counter clockwise until the motor is free.

Replacement:
Install new gasket. USE 3 NEW BOLTS ONLY! DO NOT CHEAP OUT!
!
Place motor in position, insert the allen key into the back and turn it clockwise until the motor just barely touches the gasket. DO NOT TURN IT FURTHER!!!!
Install 2 new bolts valvetronic motor to valve cover finger tight
Install new bolt at back of the valvetronic motor finger tight ONLY!
Torque the 2 bolts to cover, then torque the back bolt.
Reconnect and button up.

Retraining new/ replacement valvetronic motor.
Turn on ignition, do not start engine...wait 5 seconds, turn off ! ignition..
Repeat
Start engine, check for leaks.

3) I also replaced the grommet around the sensor and the seal around the valvetronic motor because I figured it was the right thing to do.


Still early days yet, I only finished this about 24hrs ago. But I had some good drives today. Ill post back if I run into issues!

Thanks for the continued support. Forum rocks.

[Bav Boy]

My 2006 330i started having a hard start after being parked for a long time. It would try to start but unable to latch on. But once it eventually started, it would run fine. The hard starting after prolonged parking started to manifest in shorter intervals. The code P1030 now came up indicating the valvetronic motor being stuck or sluggish. I changed the valvetronic motor but it still wouldn't start. Apparently, that was because I did not reset the ECM memory so it would learn the speed and fully open/closed positions of the new motor. A new code P1017 came up. This one was about the plausibility of the eccentric cam position sensor reading. I now tried to reset the ECM again with another method I saw in youtube. Either that worked or the ECM on its own learned the new values. The car now starts with just one tap on the start button no matter how long it was parked for.
Theory: When a valvetronic motor starts to fail, it will manifest after prolonged parking because there are two things involved now. The cold start that needs a compensation in the air fuel ratio and the increased inertia as gravity will make all the lubrication drained from the eccentric cam. Why it still would not cold start after changing the motor was because the speed on the new motor was faster that the adapted values the ECM had for the old motor. This now made it question the plausibility of the eccentric cam position sensor. With that fault active, it had to fall back to the limp home mode fully opening the motor to allow the engine to start. Now that the ECM has learned the position and speed of the new motor, all now works fine.