DIY - M271 $12 hose replacement

Subscribe
Nov 26, 2020 | 06:44 PM
  #101  
My EML light came on after a half hour drive.. then turned off.. read the error codes and i had an MAF low code and a misfire one also. That's like christmas has come early! I've been waiting for a reason to do this ever since reading this thread. i've ordered a new MAF the 2 hoses and that flexible clamp remover. I even got that click-r thing and i cant wait to tackle this, just have to wait until it all arrives. Finally a job where im not under the car, hooray!

*edit - looks like the click-r cant even be used as it wont fit unless i remove the compressor,, oh well, screwdrivers it is!
Reply 0
Nov 26, 2020 | 10:51 PM
  #102  
The Clic-R tool does come in useful. I used it on 2 connectors. One on an elbow to the throttle body, and another on where the $12 hose attaches.

The 4 hose connectors to the fuel filter also use Clic-R clamps. I replaced them with the fuel injector screw types. However, now that I have the tool, I may pop the Clic-R ones back on the next time I do the job.

With that said, check at the dealer (give them your VIN) to see if the hoses and check valve were replaced under recall. If not, they'll do the job for free.
Reply 0
Aug 5, 2022 | 10:11 AM
  #103  
First of all, thanks a lot for such a detailed tutorial!
Lately I'm getting a lot of P072 (system too rich) and P201C, plus sometimes misfire cylinder1, and rough idle jumping up and down shaking the car. I clean the error and for a while it runs fine, then back again.
MAF is new.
The hose over the supercharger is fine.
Checking the engine bay, after removing the airbox, i've seen lots of "dark oil" around that valve/hose hiding behind the supercharger.
Is there a way to check for leaks without having to remove intake and charger?
Thanks.
Reply 0
Aug 5, 2022 | 10:38 AM
  #104  
Quote: First of all, thanks a lot for such a detailed tutorial!
Lately I'm getting a lot of P072 (system too rich) and P201C, plus sometimes misfire cylinder1, and rough idle jumping up and down shaking the car. I clean the error and for a while it runs fine, then back again.
MAF is new.
The hose over the supercharger is fine.
Checking the engine bay, after removing the airbox, i've seen lots of "dark oil" around that valve/hose hiding behind the supercharger.
Is there a way to check for leaks without having to remove intake and charger?
Thanks.
make sure your top hose isn't on backwards ... one end is slightly bigger than the other, if you install it the wrong way then the fitting behing the MAF will be extra loose and will leak oil vapor ...
Reply 0
Aug 5, 2022 | 10:49 AM
  #105  
Quote: make sure your top hose isn't on backwards ... one end is slightly bigger than the other, if you install it the wrong way then the fitting behing the MAF will be extra loose and will leak oil vapor ...
Edit: found it!
Hoses are fine, they don't even look so old. Probably e previous mechanic been working on it already (a clamp is missing).
Here is the broken part. Hope I'll find a way to remove it from hose and change it without having to remove supercharger.
Hats off to everyone contributed into this discussion! Not even official dealer/mechanic looked into it.




Reply 0
Aug 6, 2022 | 05:14 AM
  #106  
Welcome to the $12 hose and broken check valve clubs.

Technically it may be possible to replace just the check valve, but you'll have to fish all the broken bits out of the 2 hoses. Also, without removing the hoses there is no way to know if you have the latest version. The $12 hose has 4 versions (different materials), so I wouldn't be surprised if the bottom 2 hoses were also updated several times.

Lastly, you'll have to somehow flex the hoses enough to install the new check valve without breaking it. If you're able to do so, please post instructions. I found I was unable to do so, which is why I removed the supercharger.

While everything is out, be sure to do all the other jobs (top up supercharger oil, change engine mounts etc.) in the link provided.
Reply 0
Aug 6, 2022 | 01:01 PM
  #107  
Quote: Welcome to the $12 hose and broken check valve clubs.
Thanks. (really, thanks a lot for this forum post, without it i don't think i'd have been able to solve by myself)
I really like this car, but damn... Who the heck decided to put that valve there?

Tomorrow I'll try to find a longer ratchet (hope its right english name) to loosen the belt tensioner, then things will get easier.
Regarding supecharger, do I have to remove only 3 bolts, correct? 2 in the front, and the one hiding down/back, right? Or also the closer one attacched to the black plastic inlet? (stupid question, but its quite difficult to reach)
Reply 0
Aug 6, 2022 | 05:41 PM
  #108  
The hoses and valve have a recall. Call your local dealer and give them your VIN. If it hasn't been done, they'll do this job for free. Recalls do not expire.

The supercharger is held together by 3 screws, 2 in front by the pulley and 1 underneath the supercharger. You are correct. However, it requires removing 2 intake mufflers beforehand, one of which is quite a pain to reach. See my link (post #1) for detailed instructions.
Reply 0

MB World Stories

The Best of Mercedes & AMG

Explore
story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

 Verdad Gallardo
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

 Verdad Gallardo
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

 Verdad Gallardo
Aug 11, 2022 | 12:40 PM
  #109  
Quote: However, it requires removing 2 intake mufflers beforehand, one of which is quite a pain to reach.
You are right! That screw hiding behind the steering column been a real pleasure both to unscrew and put back in place.

Engine bay cleaned up from all the oil/dirt, new hoses and valve.
Finally perfect idle, and looks like car is running much better.

Thanks a lot for sharing this informations.
Reply 0
Feb 7, 2025 | 05:45 AM
  #110  
W204 same problem?
Quote: **UPDATE** Had to do the job again, but this time I replaced the $12 hose and 2 lower hoses and check valve. See link.

So after reading about the many many people suffering this nasty problem, I decided to do my bit for this wonderful forum.

Not sure exactly what this hose does (it connects a metal part to a plastic part), but word on the street has it that if it springs a leak/tear, then the CEL will turn on and throw a crapload of codes (which is a bad thing :p).

The problem is caused by factory clamps that are too tight, on top of the original hoses being made of a not-so-durable grade of rubber. Left unchecked, the clamps will cut through the hose at around 70-100k km and cause problems.

All vehicles with the M271 engine (2003-2005 C230k), especially the earlier runs, will have this problem. Mercedes-Benz has released 4 (yes, FOUR) versions of this rubber hose. On my 2003, I had the 1st (ie oldest) version.

MB wants some 7h labour(!) to change this hose. Save yourself a few bills and do this yourself!

Parts needed:
A271-018-12-82-64 Hose (anything lower than 12 for the 3rd number is old)
2 hose clamps (buy from dealer or auto parts store)

Tools:

Torx T15 bit
Torx T25 bit - the shorter the shaft, the better
E10 Inverted Torx bit, ratchet set, extension (at least 3")
Hacksaw if your E10 bit is 3/8" drive instead of 1/4" drive (I hate MB )
Pliers or hose clamp remover (I recommend the latter if you already have one, but don't go out to buy one just for this one piece)
Slot screwdriver (as narrow and long as possible, this is to disengage a hose clamp)
Whatever bit you need to secure your new hose clamps
A crapload of patience and self-restraint, to prevent oneself from exploding into murderous rage while attempting this fix
A 6-pack of beer (most important tool for this upgrade, gawd was it painful)
Ice or mini-fridge for the beer
A friend/relative with functional arms
hello, does the w204 m271 still got this problem?
Reply 0
Dec 30, 2025 | 09:14 AM
  #111  
Would blanking off the vacuum port in the intake work as a temporary fix (to stop unmetered air getting in through the hoses at least)?
Reply 0
Subscribe
Currently Active Users (8)
 
story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE