Mercedes-Benz Forum banner

1 - 9 of 9 Posts

·
Registered
1995 E320 Wagon, 2002 S430
Joined
·
595 Posts
Discussion Starter #1
Cleaning the throttle body on my M104 was very straight forward and simple enough to do on our 95 E320 wagon. But on my friends newly acquired 91 300E M103, it's a completely different story with the way MB implemented the closed intake chamber (official name anyone?) that sits right on top of the throttle body, as if it were guarding it from us prying and prodding DIYers, ever so eager to get our hands in there to clean all that carbon and soot out. I am thinking I will have to build some sort of extension implement with a bristle head cleaner at the other end to be able to reach way down in there to clean everything up thoroughly. I know 3M has a product that is supposed to be able to spray upside down like that and can be combusted while you spray the carbon off with the engine running. Wondering if that would be the way to go with this setup. Also, I think I will remove the "lid" and the horizontal bracket that sits in the way. Thanks for you help guys.
 

·
Registered
300CE-24, W204 C220 CDI, W210 E55 AMG, W124 300TE, W163 ML270 CDI
Joined
·
399 Posts
Hmmm, pictures would get this going... I'm just saying.

I've always wondered how to clean it.
 

·
Registered
1995 E320 Wagon, 2002 S430
Joined
·
595 Posts
Discussion Starter #3 (Edited)
Hmmm, pictures would get this going... I'm just saying.

I've always wondered how to clean it.
HOW ABOUT VIDEO INSTEAD...


BTW, I think the Intake Snake is going to be the right tool for this job... more on that later...

My first suggestion in attempting to answer my question after giving it some thought:

1. Remove the horizontal bar atop the air inlet
2. Remove the lid atop the air inlet
3. Prop the throttle body open with home fashioned implement
4. Duct tape a toothbrush to a long skinny ratchet extension, long enough to reach down into the throttle body; spray TB with TB cleaner, brush vigorously all around walls and butterfly
5. Spray again and immediately wipe away all residue and carbon in the TB with a lint free rag tightly zip-tied to a long ratchet extension or this guy, the intake snake (looks like it was designed for this job)



6. Consider finishing up by using the 3M throttle body and intake system cleaning kit or something similar (Liqui Moly Throttle Valve Cleaner looks even better but I can't find it anywhere) wherein the engine is running while the intake is being sprayed and the carbon combusted simultaneously. Sort of like Seafoam through the brake booster but more directed to the TB opening and first part of the intake.
 

·
Registered
99-C43, 05-G55K, 71-280SL, 94-E320 CAB
Joined
·
2,282 Posts
Why not just remove the air metering assembly?
When you have it removed best to replace the rubber boot between it and the throttle body.
The boot tends to crack with age and creates erratic vacuum leaks.

The throttle body in the M103 really tends not to get that "dirty"....
The black that you see when pushing the air valve down may just be the rubber boot....
 

·
Registered
1995 E320 Wagon, 2002 S430
Joined
·
595 Posts
Discussion Starter #5
Why not just remove the air metering assembly?
When you have it removed best to replace the rubber boot between it and the throttle body.
The boot tends to crack with age and creates erratic vacuum leaks.

The throttle body in the M103 really tends not to get that "dirty"....
The black that you see when pushing the air valve down may just be the rubber boot....
Exactly the insight we are looking for. One is immediately discouraged from even thinking about disassembling the upper inlet because it appears it is attached to the fuel junction which would be a bear to remove. So my point is that just looking at it with novice eyes (the M104 is the engine I know my way around) leads one to believe it would take at least an hour just to take that inlet off with all the hardware attached to it. However, your post dispels this myth and shows that you do not in fact have to remove the fuel distributor and all 6 fuel lines. This is indeed a relief. With that inlet removed this job will be greatly simplified.

As far as this TB setup not getting super dirty, I can tell you I cleaned a great deal of carbon out of the top chamber just by itself and can see quite a bit of residue on the butterfly and just beyond it. Keep in mind the throttle body on this car has never been cleaned before. Compared to a Cadillac or a big American ugly, you're probably right in that this setup is not prone to tons of gunky buildup. I'd say every 30K is probably good to get in there and clean it out.

I don't know about you guys, but that intake snake looks pretty slick. True, you can get it done with something home fashioned ( a rag and an extension), but dedicated tools are always nice.

Anyhow know of a sticky posted somewhere for removal of the pre-throttle body (anyone know the actual name of that part?) complete with pictures?
 

·
Registered
Depends on the week
Joined
·
3,726 Posts
Why not just remove the air metering assembly?
When you have it removed best to replace the rubber boot between it and the throttle body.
The boot tends to crack with age and creates erratic vacuum leaks.

The throttle body in the M103 really tends not to get that "dirty"....
The black that you see when pushing the air valve down may just be the rubber boot....
Agreed.


Whatever dirt you do find in there, is most likely a contribution from a leaking air boot.
 

·
Registered
99-C43, 05-G55K, 71-280SL, 94-E320 CAB
Joined
·
2,282 Posts

·
Premium Member
W-1-2-3 Go!
Joined
·
16,161 Posts

·
Registered
99-C43, 05-G55K, 71-280SL, 94-E320 CAB
Joined
·
2,282 Posts
Do the fuel injector lines have to be bent (not recommended?) or do we also remove the lines together with the fuel distributor?

I've been itching to remove whole unit as well and clean the throttle body.
Fuel distributor should just lift up without bending the lines...still need to be careful.
If you're going to do it then replace the rubber boot....inexpensive and cracks with age..
 
1 - 9 of 9 Posts
Top