[IN54NITY]

First: A shout out to Wes of the old Bimmerhelp website who made the original DIY and JamesM3M5 who is a forum member. The DIY can be found as a PDF at the end of this post.

[EDIT]
May 2024: Bimmerhelp website is going down.[/EDIT]

August 2014:
I noticed about 10k miles ago that the car wasn't running as fast as it did when new and I had been getting "silent" limp modes (no codes thrown). After reading this thread http://www.e90post.com/forums/showthread.php?t=726481 I was motivated to do a walnut blast. Good thing I did. The "after" car is like driving the car new. Butt dyno says 40hp and I don't think I am exaggerating. The cleaning was tedious: walnut blast, soak with carb cleaner, scrub and now repeat about 3 times, now repeat for the other 5 cylinders! Cylinders 4, 5, and 6 were pretty bad, especially #5, where some of the sludge was 4mm thick. It drastically affected air flow.

You owe it to yourself to get this done if your car has 45k+ miles without a walnut intake cleaning!

The cool side of the N54 (with the black electronics hub - what the DIY calls the "evil box" - at bottom center):


Detail of the bottom of the intake manifold. I had a bitch of a time detaching the "evil box" (which is just an electrical hub of connections) from the manifold. (Edit: Be sure to detach this hub off the manifold before you take the manifold off the head!) You can see that I very mildly sanded the edges of the top of the lips on the two tabs so it won't be such a bitch to take the hub off it next time.


Throttle body, which I had to clean as well.


This is the actual top of the throttle body (after cleaning - sorry forgot to take pic of it dirty)


Cyl #1 intake


Cyl #5 intake - gross!


Cyle #4 with a couple blow-suck cycles, pretty clean but I gave it another blow suck.


15 Amp switch from AutoZone with wire and alligator clips. I was too lazy to jack up the car because I don't think you can turn the crank bolt from top. Edit: If you have an oil cooler you can't because there are too many hoses in the way, if you don't have an oil cooler, you can. If you take off the electric fan and its shroud - which slides up, you can get to the crank from the bottom of the car. Having a lift would make it easy. Important: For those 6MT DIYers who are about to rock, don't forget to put tranny in neutral!


Broken vacuum adapter after 4 cylinders while wiggling it out (thankfully duct tape worked for the final 2 cylinders). Wes is sending me a new one though! Thanks man!


One final note about the sand blaster kit: after getting the "40lb" pressurized sand blaster kit from Harbor Freight (i.e. the "red" media blaster kit), I found it was using waaaaay too much walnut media and I stopped using it and got the smaller "gray" portable kit that is mentioned in the original DIY link above and here: https://www.harborfreight.com/portab...kit-37025.html (kit also comes with a gun). The portable one works by pulling walnut media simply by pressure drop/bernoulli's principle of the pressurized air flow from your air compressor. I also used the "fine" walnut media which is also mentioned in the DIY.

[IN54NITY]

Ah, one other thing I did: Took the two MAP sensors (one in charge pipe, the other in the intake manifold) out and cleaned them with CRC Mass Air Flow sensor cleaner.

[chepy24]

Awesome! I'd be willing to throw some cash your way to get this done lol I'm pretty sure my car needs it haha

[Evil///M]

Good info. I wish I knew more about how the blasting tool works.

[IN54NITY]

Got a new replacement adaptor today free of charge (first one broke as I explained above) thanks to Wes. So I am willing to help other forum members. Here's the deal though: I don't want to do it on a hot car, and the job takes a ~long~ time, 4 hours. I'm willing to lend the kit out too, but if you break something, I want a new replacement for it, not $. PM me.

[IN54NITY]

Just got the Burger OCC too, and I'm about to install it at the same time I replace the pre cat O2 sensors.

Anyone already have an OCC? If so, how much oil does it collect?

[forza1976]

Wow, nice work Alex!

[IN54NITY]

Originally Posted by forza1976

Wow, nice work Alex!

Thanks! It's not very hard, just tedious. So to those who want to do it, PM me and you can do it in my garage - I have ~all~ the tools. (I will even help out [ a lot ], but you can do the scrubbing on your own damn car. ) Just bring your own walnut media (one 25lb box is plenty), shop rags (you are going to need some), carb cleaner (but you can use my CRC Mass Air Flow sensor cleaner), painter's tape and maybe it would be nice to bring a Rigid shop vac filter. You may want to bring new spark plugs too as I removing them anyways so I can more easily turn the crank and blowing out any (unlikely) walnut media that got into the cylinder. . I am not asking for any money! Just bring me a 12 pack of microbrew / nice bottle of wine (I'm a freakin' wine snob) and/or any other bribes.

[raceyBMW]

Alex, I'm definitely taking you up on this some time. I'm sure mine are nasty.

My OCC catches quite a bit, though I am also running 16-18psi.


I also upgraded the valve on the back of the valve cover from RB

[IN54NITY]

Com'on by! Thanks for the OCC pic.

[thaar]

I'm thinking my car needs this. It feels like it's become a pig over the last year or so - it could be I'm just used to the power, but I don't think that's it. Thanks for sharing your experience and the pics and offering up help. I may have to take you up on this generous offer this fall! Cheers!

[zeen]

How far are you from New Mexico? Clovis to be exact

[IN54NITY]

^ Wow. 494 miles, 7.75 hrs according to Google maps. You could make it a 'vacay'.

I'm in Louisville.

Thaar, just PM when you're ready.

[chepy24]

I'm willing to take you up on your offer my car is in need of it 70k don't think its been done once lol

[JJMEOW]

Originally Posted by aleckzandr

^ Wow. 494 miles, 7.75 hrs according to Google maps. You could make it a 'vacay'.

I'm in Louisville.

Thaar, just PM when you're ready.

Is this why you leave work every day at 3:00PM.... lol

[IN54NITY]

Originally Posted by JJMEOW

Is this why you leave work every day at 3:00PM.... lol

And I'm not even a banker or lawyer.

Originally Posted by chepy24

I'm willing to take you up on your offer my car is in need of it 70k don't think its been done once lol

Alright. This coming weekend isn't good, possibly next.

[ar design II]

Saw a few of you interested. We still offer this service for flate rate of $499

[Cacicgt7]

You have a PM

[IN54NITY]

Replaced pre-cat O2 sensors (pic below). Got a fault today for the after cat sensor. Aggggggh! Car is like taking care of nagging toddler.

If any one wants to borrow it when replacing their pre-cat O2 sensors: I fabricated a tool by cutting a notch (Dremel tool) out of a closed end 22mm wrench so that the wire just fits through (other end is open). It's such a tight fit that sometimes the open end doesn't work because the angle is just ever so slightly off.

Got mine here:
http://www.amazon.com/gp/product/B00...rch_detailpage

http://www.amazon.com/gp/product/B00...rch_detailpage

[raceyBMW]

You need to get yourself a set of these for the next time

http://www.amazon.com/Steelman-55290.../dp/B00K7YZQDK

[IN54NITY]

Originally Posted by raceyBMW

You need to get yourself a set of these for the next time

http://www.amazon.com/Steelman-55290.../dp/B00K7YZQDK

You're killin' me.



I know I could have bought those, but I couldn't find them in time so I bought a cheap 22mm wrench so I could DIY while I DIY.

[raceyBMW]

That's real strange that you got a fault on the after cat O2s after replacing the others, did you ever unplug those ones?