[TheBigYahi]

Parts Required:
2x 11367541692 $14.54 @ ECS

Tools Required:

Torque Wrench
Breaker Bar
17mm socket
8mm and 10mm hex sockets
T40 socket driver
E8 socket
Extensions galore

1. Lift up the right side of your car, wheels chocked and jack stand in place. Safety first!

2. Remove right front wheel and wheel liner (8mm and 10mm hex).



3. Remove wiring bracket using an E8 socket.


4. Locate the top VANOS check valve and use a T40 bit to remove. You will be spinning it for a lot longer than you think you should and when it's all the way out you will need to pry it out a bit to release it from the hole. I lost about a tablespoon of oil from each valve but since I'm not sure if mine were functional I can't promise you won't have more or less. There is very little room for your arm and it's difficult to locate from above. I spent a lot of time with one arm around the fender working from the top and side. Bring all your extensions and universal joints, although I found I couldn't really get the u-joints to help much.


Compared to a new valve (my valves did not appear to be slugged up like others that I've seen):


Assuming the top is the intake and bottom is exhaust (like the solenoids themselves), my exhaust side had a little burnt oil on it at the base:


5. Install the new check valve. You do not need a new o-ring, one is provided on the new valve. Torque is specified as 13 Nm on TIS but the valve is stamped with 15 Nm so I used that. 15 Nm = 11 lbs-ft. If you have access to a torque screwdriver that would be the ideal tool I think. My 3/8" 120 lbs-ft torque wrench was pretty much too big to do any good. I ended up tightening as much as I could using the T40 on an extension and then snugging with my small ratchet. Once it was snug I could confirm the torque with the torque wrench.

6. Repeat for the bottom check valve although you will have even less clearance.

7. Start engine and verify no oil leaks. I idled it for about 10 minutes and gave it a couple good rev's to be sure.

8. Put everything back together and take it for a spin.

For those without a small enough torque wrench, just snugging them down with a small 1/4 drive ratchet will suffice.

[cpie168]

Thank you for the write-up. What are the symptoms that would indicate this procedure is necessary?

[Three_thirty_I]

You beat me to this DIY! Will most likely add my DIY to your thread to keep the information in one place.

My N52 does not have that extra cable harness, so overall it should be a bit easier on mine, but looks like it's pretty straight forward as I thought. And I also don't think there would typically be so much oil spilling out, unless your check valves were not functioning properly as it's roll of being non-return valves aside from being somewhat blocked. And they do look dirtier enough for me to consider that they would affect oil flow.

Oh and now that you mentioned the 15 NM shown on the new Check Valves, I took a look the new ones that I bought still sealed in the bag, and I could actually see this now too.

Thanks for posting.

[Sample]

Can these just be cleaned, like the solenoids with maf cleaner?

[neyshule]

Yours looks fine, no sludge buildup, is there any 2A82/87 solenoid jam code?
Is removing right front wheel and wheel liner necessary? I think I can work from above, right?

[TheBigYahi]

Originally Posted by Sample

Can these just be cleaned, like the solenoids with maf cleaner?

Probably, but for the amount of effort to get them out it was worth the $30 for new parts.

Originally Posted by neyshule

Yours looks fine, no sludge buildup, is there any 2A82/87 solenoid jam code?
Is removing right front wheel and wheel liner necessary? I think I can work from above, right?

I had an intake VANOS code about 10k ago but it hadn't come back. I recently started noticing the engine stumble when going to WOT when the revs were low and I've been going through all the easy and cheap things.

There's nothing in the way stopping you from working from above, but you can't see the valves and they're recessed into the side of the head which would make it pretty frustrating to do.

[Phil325i]

Originally Posted by neyshule

Yours looks fine, no sludge buildup

+1 Can't see any reason why yours would need changing OP. Out of interest, what mileage had your car done, and how often do you change your oil?

[TheBigYahi]

Car has 113k miles, I've had it for about 20k. Previous owner gave me all the service records and it looks like he was following the CBS system. I'm doing about 10-12k, or yearly.

Long story short-ish: I had some stumbling at low RPMs with heavy throttle (lugging, I lnow) and after finding no misfire codes I started looking at the VANOS. I tried cleaning, then swapping them with marginal benefits. In my thread in the NA forum and a few others there was some discussion about the check valves. Since they were cheaper than throwing new plugs (only 20k old) and definitely cheaper than new coils I figured I'd give it a go.

One thing I did noticed was both the exhaust solenoid and check valve held much more oil than the intake side. I'm thinking it's possible the intake check valve had failed (probably only partially) and that could be slowing the action of the VANOS on the intake side. Still really hypothetical but it's felt better the last 2 days so I think it fits.

[neyshule]

do you feel any real difference after replacing it?

Originally Posted by TheBigYahi

Car has 113k miles, I've had it for about 20k. Previous owner gave me all the service records and it looks like he was following the CBS system. I'm doing about 10-12k, or yearly.

Long story short-ish: I had some stumbling at low RPMs with heavy throttle (lugging, I lnow) and after finding no misfire codes I started looking at the VANOS. I tried cleaning, then swapping them with marginal benefits. In my thread in the NA forum and a few others there was some discussion about the check valves. Since they were cheaper than throwing new plugs (only 20k old) and definitely cheaper than new coils I figured I'd give it a go.

One thing I did noticed was both the exhaust solenoid and check valve held much more oil than the intake side. I'm thinking it's possible the intake check valve had failed (probably only partially) and that could be slowing the action of the VANOS on the intake side. Still really hypothetical but it's felt better the last 2 days so I think it fits.

[TheBigYahi]

Before the replacement the engine would buck a few times if I was giving it the beans while at low revs. This usually happened speeding up in highway traffic. Worst case in 6th gear it would happen until I let up on the throttle. 3rd gear it would clear as revs came up. Since I replaced them I can do whatever I want with the throttle and haven't experienced any bucking. I'm reserving final judgement for another week or so to make sure it hasn't gone away temporarily.

[neyshule]

gooooooooood to hear that!

Originally Posted by TheBigYahi

Before the replacement the engine would buck a few times if I was giving it the beans while at low revs. This usually happened speeding up in highway traffic. Worst case in 6th gear it would happen until I let up on the throttle. 3rd gear it would clear as revs came up. Since I replaced them I can do whatever I want with the throttle and haven't experienced any bucking. I'm reserving final judgement for another week or so to make sure it hasn't gone away temporarily.

[Three_thirty_I]

That is encouraging to hear, and I hope that it continues as it is!

[Phil325i]

Just to add to the body of knowledge, I've recently replaced my check valves as a precautionary measure. As the OP mentions, access is certainly not easy as the valves are buried deep in the head. My car had done 50K miles and has oil changes at 6K intervals.

The valves I removed were in pristine condition and fully operational. You can check operation by sucking on the end of the valve when you can hear the non-return valve open and close. Changing the valves made no difference whatsoever to the operation of the engine.

My advice is, unless you have a particular problem like the OP, or your car has been subject to CBS oil changes, or possibly if you have covered a very high mileage (100K+), then changing these valves is a waste of time and money.

[Crimson335iVert]

For a noob like me, what is the function of these valves?? Sorry, I have a lot to learn about these cars yet.

[TheBigYahi]

They filter the oil and keep it from running out of the VANOS a system when the engine is off.

[Phil325i]

Originally Posted by Sample

Can these just be cleaned, like the solenoids with maf cleaner?

Yes. But it's not just a filter. There's a sprung loaded valve inside that may wear over time...

[BavarianMWfan]

I think I need to replace mine.

[Meeni]

Reposting here the same message as there: http://www.e90post.com/forums/showpo...9&postcount=54 for future users

Originally Posted by Meeni

Cool, answers!

The issue returned again with cold weather. Fault on intake vanos, does not follow the solenoid swap, made worse with cold (thickened oil) or braking (g-force induced low pressure?).

I am very interested in trying these replacement parts, they are cheap, but they look annoying to access. I tried to look for them quickly but I could not see them, I know they should be between the exhaust pipe #1 and the cam tensioner, still couldn't see.

The Bentley is silent about these. If anybody has a good DIY or access to the DIS page, I'm interested.

Ok, so I did the swap today.

Once one removes the wheel liner, it is not a very had job. There is an AC pipe somewhat in the way but it is not that bad at all. Took me maybe 20 minutes to get the swap done including the liner removal and an oil change.



Now, look at the ugly things I found in there. You'll have no problem finding which one is the faulty one, coming from the top, controlling the intake vanos. That's a lot of finely ground metal shavings. I have nothing in the oil filter, and the magnetic drain plug came out clean as well, disturbing.

I had a broken bypass valve in the oil filter housing cap, which I believe is the root of what happened here. I do not think this replacement is necessary if you do not experience symptoms like stalling with braking. Cleaning and swapping VANOS solenoids is always a first step, as is checking the crankshaft position sensor and the vanos position sensors. This is an unlikely issue that's worth investigating before going full berserk and replacing the heads.

[Dominasian335]

does any one know if it helps getting rid of 2a82 issue ? i really dont want to replace ledges.

[Dominasian335]

did the check valves, they looked clean, still get the CEL, now i noticed that it would only throw cel when the car is fully warmed up, and then when you check vanos intake and exhaust values and compare actual to dme required, you will notice that either intake or exhaust will eventually fall below the thresh hold and CEL would come up. Now it also only comes up when the car is in drive but in standing position like at the red light, as soon as the values start to drop we disengaged the AT to neutral, and values came back up. How does a vanos relates to the load in the engine. I had my torque distributer worked on, and after that issue start to come up.

[Efthreeoh]

Originally Posted by Phil325i

Just to add to the body of knowledge, I've recently replaced my check valves as a precautionary measure. As the OP mentions, access is certainly not easy as the valves are buried deep in the head. My car had done 50K miles and has oil changes at 6K intervals.

The valves I removed were in pristine condition and fully operational. You can check operation by sucking on the end of the valve when you can hear the non-return valve open and close. Changing the valves made no difference whatsoever to the operation of the engine.

My advice is, unless you have a particular problem like the OP, or your car has been subject to CBS oil changes, or possibly if you have covered a very high mileage (100K+), then changing these valves is a waste of time and money.

I plan on doing this swap soon at my next oil change. I was in the fenderwell last weekend replacing the halo bulb and finally got a good look at the job and it looks easy with the right tools. My car has 287,000 miles on it and has only ever seen CBS OCIs (averaged 17,500 miles up to 221,000). After 221,000 I dropped to a standard 10,000 mile OCI because the CBS OCI system goes defunct after the car reaches 186,000.

I'll post picks of my check valves once I pull them. We'll see if you CBS OCI theory is true.