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JRE320
05-20-2003, 02:40 PM
Just wanted to share my untimely expenses on this air mass meter. See pic below for those who don't know what it look's like and where you can find it on your engine bay. Just ignore the dirt on my engine bay.
http://ourworld.cs.com/JRE320/airmass.jpg
http://ourworld.cs.com/JRE320/airmass2.JPG
A comparison of a C36 air mass meter (left) and a regular C280 air mass meter (right)

http://ourworld.cs.com/JRE320/airmass3.JPG

JRE320
05-20-2003, 02:42 PM
Some more pics...

http://ourworld.cs.com/JRE320/airmass4.JPG
http://ourworld.cs.com/JRE320/airmass5.JPG
http://ourworld.cs.com/JRE320/airmass6.JPG

JRE320
05-20-2003, 02:45 PM
http://ourworld.cs.com/JRE320/airmass7.JPG
http://ourworld.cs.com/JRE320/airmass8.JPG

jnolte
05-20-2003, 02:51 PM
How many miles do you have on your car? Do they go out often? How much was it?

JRE320
05-20-2003, 03:02 PM
Sorry, I totally forgot to mention how much it cost. I got it at Mercedesshop.com for $265 and if u gonna get it from the stealership it will cost you like $390. Actually the one from my E-class went out on me since they got the same part number and exact application so I took the one from my C280 installed it on my E-class. So my new air mass meter goes into my C280 coz I need to have it smog and register soon. On my E-class I got like 123000 miles already.

kameraguy
05-21-2003, 08:01 AM
Jun, what happenned? How did you know it went out? Did your check engine light come on?

That sucks man....Well, good thing you were able to get it much less than at the stealership. :rolleyes:

pnsji
05-21-2003, 08:53 AM
If the idle is rough, it is most likely the MAS.
It is not always giving check engine light.

Cleaning it regularly definitely helps.

kameraguy
05-21-2003, 08:59 AM
Is there a tutorial on how to clean a MAS? If not, sounds like a good tech article ;)

pnsji
05-21-2003, 09:51 AM
Originally posted by kameraguy
Is there a tutorial on how to clean a MAS? If not, sounds like a good tech article ;)

I can start with .....

Background:
"MAF sensors can get contaminated from a variety of sources - dirt, oil, silicone, spider webs, potting compound from the sensor element itself, etc. When a MAF sensor gets contaminated, it skews the transfer function such that the MAF overestimates airflow at idle (causes the fuel system to go rich) and underestimates airflow at high airflow (causes the fuel system to go lean). This means that Long Term Fuel Trim will learn lean (negative) corrections at idle and rich (positive) corrections at higher airflow. If a vehicle is driven at WOT (Wide-Open Throttle) or high loads, the fuel system normally goes open loop with a rich mixture to provide maximum power."

pnsji
05-21-2003, 09:52 AM
Depending on how dirty is your MAS, You might need scrubbing with a soft toothbrush and some throttle body cleaner. Just spraying the sensor wire did not remove the fuzzy build-up that appeared to be small fibers from the air filter. You could followed this with some brake cleaner and compressed air to make sure there was no residue on the sensor that would attract more dirt.

JRE320
05-21-2003, 10:27 AM
Originally posted by kameraguy
Jun, what happenned? How did you know it went out? Did your check engine light come on?

That sucks man....Well, good thing you were able to get it much less than at the stealership. :rolleyes:

Chris,

I got a rough idle every morning on the first start then after the engine get hot the idle will then be back to normal.
That's when Fad and Susanto told me that my MAS is the problem.
I took out the one from my C280 and compare the part# and they're exactly the same. I installed it and see if the idle would change and yes it just went back to normal. After driving for a while with my bad MAS my engine light came on. I just reset it thru my battery. I also tried it on my C280 and as soon as I started the car the idle is going up and down. Engine light also came on. ;)

kameraguy
05-21-2003, 11:36 AM
Thanks Jun and Susanto, this has been very helpful thread. I think I may have the same problem, so I will take a look at my MAF when i get my car back. If needed, i'll give it a clean and see if it makes a diff :)

Denlasoul
05-24-2003, 09:08 PM
Originally posted by JRE320
http://ourworld.cs.com/JRE320/airmass7.JPG
http://ourworld.cs.com/JRE320/airmass8.JPG

So on this last picture, the wire "mesh" is the part that needs to be cleaned?

JRE320
05-24-2003, 09:43 PM
Not only the mesh the wire but u need to clean the middle part of it.

J Irwan
05-25-2003, 11:25 AM
Here is the pic of the actuall sensor it self..

http://groups.msn.com/_Secure/0RwDjAm8U372fyi40JhwHaeMMXYBHr!QymH0VMkAeMfuy1X0UW AN1rlg80fXJmY7wS7EPQD0vScF2GwqrntDLUcXVzK84zOxX1am z6!PMs1Y/DSC02267.JPG


That metal part is the one that I cleaned
(edit: I might have bent it around a lil bit, when I was cleaning it. That probably that srew it up , I am not sure :p )


However read this: I tried to clean up my MAF but i think I ended up screw itup badly... (it won't work as it supposed to anymore)
so becarefull...
http://groups.msn.com/_Secure/0RwCpBG4Uob2fyi40JhwHabqJqYMJK9ZBHoA!uu0W!DYCu3l!M 7TZLIM9m3ab1roBPeVHU8ARpQZxOigEsPS7LXD8OXER*5WMfK7 AlCdyn5w/DSC02266.JPG

This is the other side of the sensor:
http://groups.msn.com/_Secure/0RwDeAm8U4L2fyi40JhwHaZgF!E1AuQND9aYTuLUngqrEeLTcO XasKrdv4eJ9!Gsf0v8bzJ*Y3RKZVTXPGJmUuUXoSpyA3d!0*!8 C2C7x!Dk/DSC02276.JPG


Probably because I I decide to pry out some of the cover so that i can have better access to that metal piece to clean it.

http://groups.msn.com/_Secure/0RwDeAnAUHb6fyi40JhwHaVNMA4Vz!qYj4HxsL!km7y4*6ezXB EM9i8uDy2lt8ad4COAkKxlbFFM52RnOoIbEJ4bmHWlueBKFyKa aUF99Ut0/DSC02268.JPG
I use rubbing alcohol and Q-tip to clean it. It was a bit dirty.


Just to give you better pic of what is going on, Here is the MAF housing without the sensor in it
http://groups.msn.com/_Secure/0RwDeAmkUbLyfyi40JhwHaRQDd08F7tTIh!40GCr4iy!!lV9z6 7m7HaJuSGlBJ*eqJygdMul1L2CnzQfdrP3I1YSY!l*QYB1d!Gc ysZkX0lE/DSC02270.JPG



Take your own risk when cleaning out your MAF.
I would clean it when the MAF start acting up, that way when you break it you got nothing to lose, you got to buy a new one anyway.


Here's is a tip:
If your still running fine, I personally wouldn't mess with it or even try to clean it


Hope this helps.

Regardz,

J Irwan

J Irwan
05-25-2003, 08:46 PM
Also


Be very carefull choosing aftermarket intake...
other wise you get exessive oil on the sensor and it will fail prematurely.. !!!!



Regardz,

J Irwan

JRE320
05-25-2003, 11:33 PM
How did you unscrew the sensor out? It seems like you need a special tool for it. :confused:

J Irwan
05-25-2003, 11:55 PM
Jun

you need the special torx screw driver. (they call it "security torx" head)..


Although on my new MAF (this is when MB changed the new part number) they put security star screw :mad: ...



Regardz,


J Irwan

JRE320
05-28-2003, 02:05 PM
that's what I saw. star screw and I was wondering how you get that sensor out. Anyway thanks for the info. ;) :)

kameraguy
05-28-2003, 02:41 PM
On a C36, or other 202, what's the second connection on the cross-over pipe, towards the rear before it bends into the engine?

Is that a second sensor of some sort?

Like on Jeremy's 95 C36, he has the air sensor as Jun shows in his pic, as well as a second connection on his crossover pipe (which says 3.6). i'm sure you guys know what this is, since I can't describe it any better :p

For whatever reason, my car doesn't have it! Menaing i DO have the hole, with a plug in it, but no wire connected to it!

I was wondering what would happen if i don't have that sensor. My car runs fine, and I haven't had any engine problems, aside from an intermittent rough idle at a stop. But not too often.

I'm pretty sure the body shop who worked on my car f'd up and didn;t reconnect this....where does the wire go? I'm trying to find it :p

J Irwan
05-28-2003, 03:28 PM
Originally posted by kameraguy
On a C36, or other 202, what's the second connection on the cross-over pipe, towards the rear before it bends into the engine?

Is that a second sensor of some sort?

Like on Jeremy's 95 C36, he has the air sensor as Jun shows in his pic, as well as a second connection on his crossover pipe (which says 3.6). i'm sure you guys know what this is, since I can't describe it any better :p

For whatever reason, my car doesn't have it! Menaing i DO have the hole, with a plug in it, but no wire connected to it!

I was wondering what would happen if i don't have that sensor. My car runs fine, and I haven't had any engine problems, aside from an intermittent rough idle at a stop. But not too often.

I'm pretty sure the body shop who worked on my car f'd up and didn;t reconnect this....where does the wire go? I'm trying to find it :p


From the look of it, it was intended to be plugged from the beginning..
maybe the MB engineer was thinking about some add's on performance ... later on..

hint:hint: NOS sprayer.. would fit in there.. (so you could run NOS with stock airbox :D)


Regardz,

J Irwan

kameraguy
05-28-2003, 03:31 PM
So J, does this mean your car doesn't have a connection either?

i'm confused :p

BenzMeister
06-09-2003, 03:22 PM
Originally posted by JRE320
Just wanted to share my untimely expenses on this air mass meter. See pic below for those who don't know what it look's like and where you can find it on your engine bay. Just ignore the dirt on my engine bay.
http://ourworld.cs.com/JRE320/airmass.jpg
http://ourworld.cs.com/JRE320/airmass2.JPG
A comparison of a C36 air mass meter (left) and a regular C280 air mass meter (right)

http://ourworld.cs.com/JRE320/airmass3.JPG
The AMG MAS is not compatible with the C280 MAS?

pnsji
06-09-2003, 03:47 PM
Originally posted by BenzMeister
The AMG MAS is not compatible with the C280 MAS?

because of the year.
If it's the same year, should fit just fine.

BenzMeister
06-09-2003, 04:04 PM
Originally posted by pnsji
because of the year.
If it's the same year, should fit just fine.
So a 99 AMG MAS should fit my 99 C280, thanks.

JRE320
06-09-2003, 05:28 PM
Originally posted by BenzMeister
So a 99 AMG MAS should fit my 99 C280, thanks.

Why don't you try taking them off and compare the part numbers.. ;) That's how I found out that my air mas for my C280 and E320 are the same. ;)

BenzMeister
06-09-2003, 05:35 PM
Originally posted by JRE320
Why don't you try taking them off and compare the part numbers.. ;) That's how I found out that my air mas for my C280 and E320 are the same. ;)

Good Idea thanks:)

kodiak
06-11-2003, 04:46 PM
In the picture of the MAS sensors above the difference is not C36 versus standard M104. The sensor on the left is for an ODBII car 96-00 W202 and the sensor on the right is for a non ODBII car 94-95 W202. My 95 C36 has the sensor on the right.

Oh and we should note that 9 times out of 10 the MAS is being fouled by an over oiled K&N air filter. (raises hand) I am looking into other performance filters currently (ITG, etc) and let you know what I find.

~dnm

BenzMeister
06-11-2003, 06:14 PM
Originally posted by kodiak
In the picture of the MAS sensors above the difference is not C36 versus standard M104. The sensor on the left is for an ODBII car 96-00 W202 and the sensor on the right is for a non ODBII car 94-95 W202. My 95 C36 has the sensor on the right.

Oh and we should note that 9 times out of 10 the MAS is being fouled by an over oiled K&N air filter. (raises hand) I am looking into other performance filters currently (ITG, etc) and let you know what I find.

~dnm

Yes, people have a tendency too over oil K&N, I've used them in all my cars for a decade and never have a problem. Trick is, after you clean the filter, just put a few drops of oil between the seams and let the filter stand for 15 to 20 for the oil to absorb. even then I take a towel and gently wipe the filter down for any excess oil. Never had one fail yet. One other thing, unless you live in the sand there is not need to clean them more then once a year

CTOWN-BENZ
06-19-2003, 06:02 AM
For those that have an ODBII car, codes P0171 and P0173 are a tell tale sign that your MAS is failing. When the check engine light goes on, just have the codes read to be sure.

I just went through this last week, but fortunatly, my car is still under warranty.

19000 miles!

Completely stock, no K&N.


-B-

speedybenz
07-02-2003, 11:45 AM
The picture of J Irwin's MAS sensor, side view shows there is a peice missing. There should be plastic cover on the bottom that would enclose the side of the MAS sensor to direct the air up into the metal strip.

Also to clean mine I remove the sensor and spray it with Carb Cleaner, like 1/2 a can or more and then spray it with Brake Cleaner, again 1/2 can or so to remove the carb cleaner residue.

Jeff