[DIY] E70 4.8i Throttle Body Cleaning
 

This is an easy, half hour job at most. And it is good for preventative maintenance. I don't know where the throttle body is located on the 3.0 or 35i, but the process would be very similar.

Tools you'll need:

(1) flat-head screwdriver
(1) can of throttle body cleaner
Lighting of some kind

First, open the hood.
http://i284.photobucket.com/albums/l...e%20Body/1.jpg

Next, we lift the aesthetic engine cover.
http://i284.photobucket.com/albums/l...e%20Body/2.jpg

Now we need to remove the tubing/resonator that connects the intake manifold/throttle body to the MAF tube/sensor. There are two hose clamps that take a small flat-head screwdriver to loosen and remove. The first is at the coupling of this tube to the MAF tube. Loosen this clamp.
http://i284.photobucket.com/albums/l...e%20Body/3.jpg

Pull tube towards front of vehicle.
http://i284.photobucket.com/albums/l...e%20Body/4.jpg

The next clamp is both difficult to see and to get to. Here is the location, just follow the bottom of the tube down.
http://i284.photobucket.com/albums/l...e%20Body/5.jpg

Insert the flat-head screwdriver at this location.
http://i284.photobucket.com/albums/l...e%20Body/6.jpg

You'll want a work light of some kind. You're trying to slot it into the clamp screw here.
http://i284.photobucket.com/albums/l...e%20Body/7.jpg

Once loosened, pull the tube towards you and set aside.
http://i284.photobucket.com/albums/l...e%20Body/9.jpg

Now you have a clear view of the throttle body.
http://i284.photobucket.com/albums/l...%20Body/10.jpg

http://i284.photobucket.com/albums/l...%20Body/11.jpg

You can push the top of the butterfly valve blade to rotate ~90 deg.
http://i284.photobucket.com/albums/l...%20Body/12.jpg

Use throttle body cleaner.
http://i284.photobucket.com/albums/l...%20Body/13.jpg

Spray the cleaner on all exposed areas, then wipe with paper towel or shop rag. Rotate the blade, spray more cleaner inside on metal parts and clean this as well. Get a new rag and repeat the process for good measure.
http://i284.photobucket.com/albums/l...%20Body/14.jpg

Clean throttle body (and ripped glove).
http://i284.photobucket.com/albums/l...%20Body/15.jpg

http://i284.photobucket.com/albums/l...%20Body/16.jpg

Now put the throttle body tube/resonator back on and secure both hose clamps the same way you loosened them. Replace engine cover.

Turn on the car and let idle for a few minutes to burn off any of the cleaner that made its way into the intake manifold. You may notice a bit of a stutter at first, but this is just the excess cleaner burning off.

You may or may not notice any measurable difference in throttle response, but this is good for routine maintenance if you're outside of warranty.

I wouldn't do that man. Ruin the warranty. Take it to a certified technician for sure. Also, pic #7 looks really bad, perhaps get a better photo for us?

thanks! this will be helpful once the warranty period is over =)

Did this over the weekend, super easy and an awesome DIY writeup.

Gas milage is up, idle is much smoother, and gear shifting is a bit smoother as well.

Since this does effect shifting I also suggest the tranny reset for those like me with a way dirty TB.

Thank you Finagle69!!!!

How do you reset your tranny?

Insert key, push gas pedal all the way down, press the start button (do not have the brake pedal pressed at all) and hold the gas for 35 seconds. Let go step on the brake and start up :)

Glad I could help. And yes, tranny reset is a good thing to perform after this.

In the US, the dealer needs to prove that any damage done was a direct result of what you did. Please elaborate on what possible damage can be done, by cleaning the throttle body?

1. Agree with the concept that cleaning a throttle body cannot damage anything and cannot impact the warranty....

But.

2. The comment about "the dealer must prove" is real nonsense. Yes, Moss Magnussen is the law, but PRACTICALLY speaking, dealers hold all the gold: they just need to decide something you did caused the damage and YOU are stuck with mounting a lawsuit! It will cost you $40-100k to sue them, for a disagreement over a an engine or tranny worth 6, 8, 15k. In reality, most people just give up once the dealer/manufacturer takes a hard stand.

Yes, a bit OT, but lots of people repeat this factoid and don't appreciate the practical aspects.

I'm gonna revive this thread as I'm interested in doing this for my car.
Are you sure that it's ok to touch/move the butterfly? I've heard that it could damage it