- Mercedes Benz C Class How to Clean MAF Sensor and Throttle Body
Step by step instructions for do-it-yourself repairs
Browse all: Air Intake and Exhaust Guides
Maf and throttle body clean w203 m112
If you use (minimum possible) less oil than required:
* The sensor might survive years
* The filter will in mild driving conditions (2% by population) need monthly cleaning
* In average driving conditions it will need weekly cleaning
* Most HARSH (dust, sand, track) driving conditions require daily filter cleaning
* Failure to vigorously maintain the K&N filter, and you may as well drive with NO filter.
IMO: For the cost / hassle / worry, may as well use a top quality stock filter
FYI:
As a professional mechanic performing PPI = Pre Purchase Inspections.
The (durability) value of any vehicle drops significantly when K&N filters are found.
whunter@pelicanparts.com
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Last edited by Ivanrad; Jul 31, 2013 at 07:12 PM.

How does K&N (or any other such type) filter can wreck the MAF even when little oil is used?
What is the mechanism of the wrecking or damaging? I just can't imagine how.
If K&F fitler is not maintained, say too much dirted, how would it be considered driving with NO filter? What's the mechanism or logic behind that?
BTW, I have OEM paper type filters (2) in my C230.

Just some dirt getting through the filter can damage a MAF. Stick to good OE filtration. Benz filters are excellent.
This car is stumbling but there are no misfire codes or O2 sensor codes.
You say there are no air leaks on the inlet system, airbox & MAF
You need to check all vacuum pipework & breathers for leaks. If you did not disturb them it is unlikely.
You are getting MAF codes which is why I think the MAF is on it's way out.
You could have more than one thing wrong.
Here is a sad tail of MAF cleaning that lead us on a merry dance. This MAF failed after cleaning.
https://mbworld.org/forums/c-class-w...ht=cleaned+MAF
Just some dirt getting through the filter can damage a MAF. Stick to good OE filtration. Benz filters are excellent.
This car is stumbling but there are no misfire codes or O2 sensor codes.
You say there are no air leaks on the inlet system, airbox & MAF
You need to check all vacuum pipework & breathers for leaks. If you did not disturb them it is unlikely.
You are getting MAF codes which is why I think the MAF is on it's way out.
You could have more than one thing wrong.
Here is a sad tail of MAF cleaning that lead us on a merry dance. This MAF failed after cleaning.
https://mbworld.org/forums/c-class-w...ht=cleaned+MAF
could I please have the diagram of the vaccum lines .
The Best of Mercedes & AMG
* Restarted her 15 mins ago and i feel as if the car is shifting with the direction of the cylinders. this makes me think its motor mounts.
* the maf is disconnected while this is happening so its not the maf
* Something popped off like a vacuum tube that's it or motor mounts
Last edited by Ivanrad; Jul 31, 2013 at 11:17 PM.

Cancel codes & drive the car to see what comes back & report here.

What's the mechanism of the failure between the MAF sensor and the CRC cleaner?
If cleaned as instruted, NOTHING touches the sensor other than the CRC cleaner liquid stream of the sensor. Is there some kind of chemical reaction happening begtween the CRC cleaner and the MB Bosch MAF sensor?
I've used CRC MAF Sensor cleaner on following my family/friends cars over the years as a "routine" maintenance:
MB C230
MB SLK280
Hyundai Accent
Hyundai Sonata
Toyota Celica
Toyota Camry
VW Golf
Acura RSX
I did NOT wreck any of the MAF sensors by cleaning them and some their MAF sensors are Bosch brand that MB uses. In fact, all of them drove MUCH better after cleaning,
, way better throttle response, except the Accent. The MAF was bad BEFORE cleaning. So the cleaning didn't do any good on that car. It was just an attempt.

If it causes a failure that MAF would probably have failed in the next 10K miles anyway.
As I said above. Old MAF's often fail when cleaned.
EDIT: The worst thing you can do is spray MAF cleaner on a hot MAF.
Last edited by Glyn M Ruck; Aug 1, 2013 at 03:49 PM.
If it causes a failure that MAF would probably have failed in the next 10K miles anyway.
As I said above. Old MAF's often fail when cleaned.
EDIT: The worst thing you can do is spray MAF cleaner on a hot MAF.
Oh yeaah lets just shove the throttle body completely behind the block . Oh even better lets give people less then an inch to move their hands around.
anyway that rant is over.
Can I please have a picture of the vaccum lines on a jpeg of the real engine. I can't even tell if that drawing is from a kompressor or my engine. Glynn I owe u the world for your help. I just need some pictures and more guidance on inspecting what is wrong

Please also clean the MAF plug with switch cleaner.
Good luck!
How many miles on your 'Stang's MAF?
Sorry ~ Benz cars are not American crude iron. Rant over

Checked as many hoses as i could see i used my mobile phone. i still cant identify which hoses are part of the vaccumm.
I took apart everything. covered the plenum with plastic bags till i can figure this out. when i shake the throttle body lightly i hear a click like something is falling into place. shouldnt everything be solid?
the elbow with the maf in it is slightly shaky. i was wondering if i could seal that better.
i didnt really overtighten the throttle body because it was easy to remove. what is my next step?
also the plenum to the throttle body usually has a gasket.. i guess this gasket is gone and i need a new one?
should i remove the plenum and just clean it?
where in the world is the CPS?





I double checked the install and i don't hear a vacuum link
any tips will be helpful. its not the maf because i disconnected the maf and still the same sound

The CPS is at the rear of the engine below the LHS cylinder bank looking from the drivers seat.
When you cleaned the throttle body did you clean the actuator properly as shown in PA Pete's link?
http://s8.photobucket.com/user/tause...O0026.mp4.html
video of sound





