[zsiy53]

Disclaimer: I am not an expert by any means. I just like to figure problems out and then fix them. With that being said, I am just sharing my experience with you and you will operate at your own risk if you decide to give it a try.

Background: I was driving my 09 E93 (N54) on a highway about three weeks ago, and I got a warning message stating engine malfunction, reduced power. I did some research online after I got home and found several BMW owners said that the charge pipe might be the cause because it’s made of plastic and may blow up in the worst-case scenario. I immediately checked mine and found some oil leaks on the pipe (no idea where it came from but seems to be there for a long time), so I decided to upgrade it with aluminum pipe with BOV (looks and sounds cool). In addition, some people point out that air leaking in vacuum hoses, bad spark plugs, vanos solenoid, injectors or HPFP can also cause engine malfunction. I was hoping it’s not injectors or the “famous” HPFP issue because they are expensive to replace. By the way, I called BMW NA customer service regarding another recall and asked about the HPFP and they told me that they extended the HPFP warranty to 10 years or 100k miles. If someone can double-check and confirm that’d be great.

After all my research, I decided to clean vanos solenoid, replace all the vacuum hose (including the booster vacuum hose as I found it starting worn-out on the front side), replace spark plugs along with charge pipe and air intakes.

Below are the tutorial videos I followed and my experience. Hopefully it will be helpful to someone:

1. Clean vanos solenoid: The space is very limited and you can drop the bolts easily. So just put a rug or something underneath just in case. Make sure they are totally dry before you put them back. Replace them if they are bad. I had a hard time putting the bottom one back so what I did was placing it into the right position first and then connect it back to the wire.
Tutorial:

2. Replace spark plugs: it is pretty straightforward but just remember to get the 14mm thin wall socket. If it comes with magnetic, that will make the process much easier. The last two spark plugs are probably the hardest ones to take out because the space is limited. Just be patient.
Tutorial:

3. Replace vacuum hose: Ne1man35 explained the layout of the vacuum hoses very well. The top two hoses from the top of the vacuum canisters are very straightforward. The ones from the bottom are a little bit tricky. What I did was taking off the three bolts on the vacuum canister holder and flip the canisters over (see the first attached picture). Pulling off the vacuum hoses are difficult. Using a razor blade to cut the stock hoses vertically around the nipples will make the job much simpler.
Tutorial:

4. Replace booster vacuum hose: this is the thick vacuum hose that goes around the stock air intake box. It looks very simple but I spent quite some time on it. I thought I could just pull it out from the connector but guess what, I couldn’t. The reason was that there was a white plastic ring thing (not sure how to call it) embedded in the rubber that prevented it from pulling/falling out. I couldn’t find a better way around it other than destroying it. If you have to do the same as I did, try to break one side and then pull the rest out gently (remember it’s a ring). See the second attached picture.

5. Upgrade charge pipe with BOV: if you decide to upgrade your charge pipe, I strongly recommend you to get the one with BOV. It just sounds so good. If you get BOV, install it on the pipe before you put it into your car. Place the bottom in first and adjust for the top. Also, get a 4mm - 6mm vacuum hose for your BOV. 3.5mm will be too tight, and you will need two ⅞ - 1 inch cap covers for two holes. Rubber chair tips will do.
Tutorial:

6. Install dual cone air intakes: this is the easiest and least time-consuming part among all. All you need to do is taking off the stock air intake (you have to do this anyway if you need to replace the charge pipe) and insert the cones in. You want the clamps to be tight but don’t over do it.
Tutorial:

7. Change PS fluid: my wheel was making noise after I drove through a heavy rain. The first thing I did was checking the PS fluid and it turned out to be low. I ordered a 1L CHF 11S (if you are not sure, check the PS cap) but the noise went away the second day before I changed the fluid. I ended up changing it anyway since it was low. What you will do is: 1. Get the stock fluid out using a pump transfer; 2. Pour about ⅕ of the new fluid (looks green) in; 3. Start your car and turn the wheel to the lock position (both left and right); 4. Turn off your car and suck the fluid out; 5. Repeat step 2-4 for another one or two times. I did three flushes in total just to make sure I had all the old fluid out.
Tutorial:

I’ve been driving my car for about a week now, and I can tell it’s much smoother and has more power than ever before. The intakes and charge pipe do make a difference, and I really enjoy it. The next thing I’m planning to do (probably next month) is the MHD stage 1 flush. I’ve heard a lot of good things about it and want to give it a try. However, many people report that they have misfire after the tune. So I’m planning to replace the coil pack (the cone looking thing you have to take out before reaching to the spark plugs) before the stage 1 tune just to avoid any hassle down the road.

[ibd12nv]

Great post thanks!