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@S-Prihadi Pak Surya, again many thanks for sharing your extensive insights, man I learned a lot from this forum
I will ask the mechanic to check also the fuel vapor system and other parts, but my first step is to replace PCV system and hope it will improve my long term fuel trim. This morning the long term fuel trim is little bit improved than usual. The imbalance between bank 1 and bank 2 makes me suspect its the PCV system.
I already replaced gasket #40 and #120 x 2, maybe that also contributes the improved long term fuel trim (previously lowest I can get is 10%, and during the traffic was 12% or so)
PB auto is recommended? their price is very good, However I doubt its really original/genuine as their pricing is lower than fcpeuro. It even cheaper than my local indie which claim their part is OEM, no MB logo. Can you share details of your local indie?
PBauto is only selling genuine MB parts when they stated ORIGINAL / GENUINE, otherwise it is aftermarket or OE as used by MB.
That been my experience with them, but I have not yet bought plenty of genuine parts from them.
MB Genuine serpentine belt tensioner, I checked the tensioner and the box barcode + QR code, all good. Older stock in May 2024, was Rp1.26mil
The simple plug, that is aftermarket
Same serpentine belt tensioner from a US MB Dealer, equal to Rp1.55mil only.
Since the 2 belts guide pulleys are not MB genuine from PB Auto , which they show , I bought genuine ones then at Mercindo Toped which was discounting it good.. https://www.tokopedia.com/mercindo/g...z-100-original
I paid a bit lower back in May 2024
This guide pulley at MBPartsExpress is US$56+-
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PCV system , this so called valve, which is actually an oil and air separator, its seal do get worn out. See the left one , the seal has gone wide.
This item at 14 years , while only 70,000KM, best you replace all.
Plastics parts on any car, when it handles oil, coolant, hot 90C gas .............. it has a fixed service life. 14 years is good enough.
This is my 10th year BOUGHT list, from buy list to BOUGHT , many I have replaced\installed, some I am waiting for yerar 11th or 12th,
due to the amount of work required accesing the parts I wanted to replace: https://mbworld.org/forums/e-class-w...rts-renew.html
I don't want breakdown, I estimate parts life and feel happy if I can replace them well before they break apart or don't feel tight anymore or not behaving like new.
The key for me is, my car must feel new at all times...while I do rough it up a lot.
The only components I can not predict with certainty are the electronic modules. ECM, tranny computers inside and outside the tranny and ABS computers.
Your ECM I believe is ME 9.7 family, if it survive to 20 years, you can open a bottle of champagne for celebration.
The capacitors is one of the weak link and on any ECM fo that matter and ignition driver circuit too it seems.
Why ME 9.7 has the famous nickname in Indonesia as the Grilled ECM ( ECM Panggang ) , it is due to its high failure rate compared to Japanese cars ECM of the same age.
To me any ECM like ME 9.7 and SIM271 of M271 EVO engine, these two ECM houses the driver circuit for the COPs and that is high electrical and heat load.
Newer ECM only send out low power trigger signal to newer COPs with built-in driver circuitry in each and every COP, thus electrical load in newer ECM like mine MED177 is not as high as in
older ME 9.7 and SIM271.
BTW many Japanese cars , their designers have the brain power to place ECM at cooler location.
An example here a 2010 Lexus RX350 ( Harrier for us Indonesian ) , hidden INSIDE the car close to glove box, that means car AC helps to cool it down https://www.clublexus.com/forums/rx-...010-rx350.html
M272 / M273 and my M276.8 3.0 Turbo is the same dumb-azz placement of ECM, a grilled ECM.
As your E300 is aging, non metal parts on it, will demand more parts replacement due to "oxidation" at age and heat, no way around that.
If you want to keep it to 20th year, expect to see more parts falling apart for the next 6 years.
Where you are now, is about the same as my friend's W204 of year 2010.
@S-Prihadi Thank you again for sharing your experience on local tokopedia and share your local indie info. greatly appreciate it.
As the parts, finally I replaced all of the PCV system. The owner of the indie re-confirm to me, are you sure sir you want to replace all of this? not only change the leaking only? I said yes I'm sure, its 14 year old car, its normal plastics and rubbers to age. She did ask me also, where did I get all of this part number, not many of of our customer has this detailed part no info. Some of it first time she ordered. Of course I tell her this forum
Below is the part number I replaced yesterday, all claimed original MB except no. 3.
On top of that I told the mechanic the noise (when the engine is cold) after replacement of auxiliary belt last week (on another workshop), please also change the idler pulley or tensioner if required. After replacement of the idler and tensioner the noise persists, so replaced the belt again with original MB one. Previous one was continental brand, I thought continental is good?? well the noise is gone now.
Now the fuel trim figures, it seems improved. LTFT now sitting at 4.6% on bank 1 and 2.3% (improvement from previous initial one at 12.5% and 7.8%!
It seems when in neutral the short term fuel trim its on negative value, when in gear (also stopped) on 0.7%. when driving it fluctuates a lot. I did record/log it on the launch, and can view the recording on the launch, but I dont know how to export the data to PC ) I did try to plug it to my pc but nothing happens.
Should I chase it more to get it to 0%?? what other parts hmmmm. o2 sensors maybe?? With this little number will it show on the smoketest? (if I ever could find a workshop which can do smoke test)
btw this is the one of the example of the part, how to check whether its original or not? is this really original? cant scan the QR code the rubber part has shrink in size not as bad as others I saw online
Last edited by tesna; 09-11-2024 at 08:46 PM.
Reason: add more
Good info.... things are improving on your car. I am happy.
01, This is genuine by its barcode and QR code. I just scanned it.
The QR code, where I marked green, that is the P/N being scrambled in a fixed sequence.
The scrambling
Orange box is how the arrangement of the scrambled number is to be read or converted back to its normal arrangement.
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Most indie will want to only replace parts when they are bad/broken/defective, because owners 99% do not know about cars and does not understand preventive maintenance.
Most owners only know corrective repair. Therefore if an indie offers or advice too many aging preventive parts replacement, they may sound like trying to "up-sell" and may seems like
a rip-off. That is the problem.
We as owners and a car enthusiast must know our cars and its wear and tear components and its weakness, if we want long term troublefree ownership.
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Fuel trims
I am not suprised the fuel trim logging is not something you can export out of the baby launch. At the least you can log it, can it do 30 minutes ?
Come to think about the emission test machine, if it were Rp10mil or US$650, I would love to buy one, but at typical Rp30mil and up or u$2K or more, I rather pay the
US$10 for the emission test, just to compare our engine Lambda reading to the test machine, while also getting 3 other gases readings.... so dirt cheap
So use the emission machine as our 3rd party test tool.
I suggest you set back the fuel coding to its original and do emission test again, before replacing the 4 o2 sensors.
You data log each when each corrective measure done, because its more than a few components on your engine which has aged or drifted.
Emission test machine Lambda reading must show stoich value, like 1.01 at the least.
When doing intake work and PCV system refresh, resulting in improvent in LT fuel trim, that is a good sign where indeed the repair is actually needed.
Chasing ST fuel trim to zero% is not too important if you can get as low as under 1%....of course seeing lots of zero % at idle is nicer.
---------------------------------------------
As for the repair kit from FCP Euro
The oil cooler gasket ( get it from MB Indonesia ) is the only one I would reccomend, as that gasket when leaking at the wrong region, can cause engine oil and coolant
to mix. I am also replacing my equivalent gasket for oil cooler latest year 12th, it is just that the work on my engine to do so is a nightmare
The 4 magnets while mine has been replaced out of caution because if oil leaks out to wire harness, ECM can wick oil from these 4 magnet and 4 of the cam position sensors.
I have not replaced my 4 cam-pos sensors because it has the latest ( supposedly safest ) part number. My magnets was not of the latest/safet P/N.
.
Engine oil cooler has four "holes" 2 holes are IN-OUT for oil and 2 other holes are IN-OUT for coolant.
While engine running, pressure of oil can be 55PSI, pressure of coolant hardly exceed 20 PSI at WOT.
When engine shut down, oil press is zero, but coolant press can stay 7PSI till it cools down.
3 mode of leaks, oil or coolant leak out to floor and the last scarry one is both oil and coolant leak at gasket but they cross-feed each other, there u get the cocktail.
Oil cooler gasket WILL LEAK for sure, it is a matter of time only.
As for metal core of oil cooler, it can also leak out or cross leak between oil and coolant. If your original MB coolant is good, I would say 20 years life out of engine oil cooler metal core is easy.
BTW, 14 years today, have you replaced your coolant and the coolant reservoir tank ? That tank has chemical bag which why MB original coolant can last 15 years.
I have replaced my coolant tank and my coolant is never older than 5 years.
Do note : You probably can noy buy the blue MB coolant anymore, it will be pink. They stop selling blue one late 2023.
These two different type coolant can not mix, so when you flush the old blue coolant, you must also use distilled water and run engine on it for say a few hundred KM and then flush it well,
and use the new pink one.
whoa @S-Prihadi thanks for the confirmation of original parts or not, since I scanned on my phone it does not detect anything . So that indie can be trusted then (I hope) . I will order next parts from them again for sure, as they are close enough to where I live and work and have competitive price.
The baby launch can log 30 minutes and more, however so far I only able to play back it on the launch device itself. Cannot figure it out how to export it. Perhaps I'll use my bluetooth obdII and connect to my phone if really want to log it. The fueling config now back to basic value since a while ago (octane and AFR)
... Poor performing sensors will cause the ECM to shift fuel trim towards rich which causes spark plug fouling. It's good practice to replace the plugs at the same interval. ....
Which I've been experiencing so far, it might bring my fuel trim further down. That will be my next target for replacement I guess, along with oil cooler gasket
I have replaced the coolant few months ago, not sure about the color since I did not stay at the workshop. They use 4 bottle of it (mix with distilled water 1:1 ratio). Not sure if they did flush it totally with distilled water, but I did not drive it few hundred KM on distilled water for sure! Perhaps I will reflush it again when I replace coolant reservoir tank
see the coolant color at your coolant reservoir..... by P/N of the photo it is blue one.
If it is blue, lucky you they still have stock of blue one.
So no need to flush it out. You can use it for a long time.
In 2010 MB would be using the older yellow color, same as my 2014 E400.
That yellow one long gone already...LOL.
is it ok to put different part no for upstream oxygen sensors? When I come to the workshop they said ok to use this, been installing on several e300 and works out fine.
I look it up its for E400. For the exact part no for M272 they dont have in stock, even at MB dealer. I checked also other indie no one has them in stock 🥲. Some has oem named pierburg. So o2 sensors replacement is now pending
I dare not reccomend you to use front wide band o2 sensor from an E400 ( M276.8 ) which is of different P/N compared to M272.
I fear that M272 is using LSU 4.2 , while my engine is using LSU 4.9 and these two are rather different.
If M272 front wide band o2 sensor is not using Bosch family, that is even higher risk.
I dare not reccomend you to use front wide band o2 sensor from an E400 ( M276.8 ) which is of different P/N compared to M272.
I fear that M272 is using LSU 4.2 , while my engine is using LSU 4.9 and these two are rather different.
If M272 front wide band o2 sensor is not using Bosch family, that is even higher risk.
Be patient, order all 4 o2 sensors from FCP Euro, in 2 weeks you will get it, sometimes a bit faster.
Wide Band o2 sensors are very very vehicle specific.
I rather you play safe.
okay, thats for the re affirmation. I will order from fcpeuro 👍 However is it ok if I use bosch? mb oxygen sensors for m272 is 360 usd each on fcpeuro 🤦♂️. The bosch one is almost 1/3 of it.
Originally Posted by S-Prihadi
My front wide band is not the same P/N as your photo.
As used on the car.
BOSCH, OE
You don't have photo of what P/N front wide band o2 is on your car ?......yet
well I just look it up the part number on google and e400 was one of the results. Also used in C43 etc
of course I haven’t got mine yet. Gosh maybe I have little OCD to make everything runs great on the car, ever since I got bad emission results its been haunting me 💀
If genuine Mercedes-BOSCH : https://www.mbpartsexpress.com/oem-p...ensor-35427018
If MB branded goods, FCP Euro is always more expensive than typical MB official dealer like MBParts Express, hence you see FCP Euro charging US$100 extra.
But remember, MB official dealer does not ship goods out of USA and limited lifetime warranty.
Happy shopping and don't forget to inform FCPEuro your Indo Tax ID.
NOTE : FCPEuro has 2 warehouses in USA. Their online website is not live linked to their warehouses computer system.
Do not make correction or add-on order towards an already processed order in their website, their system could produce error. I had such a case with M271.8 EVO parts.
So choose what you want, confirm it and done deal, don't make correction.
Shipping out of USA to you, max US$45 for such small package of 4 sensors.
-----------------
I like your ethusiasm for chasing down HC level. Yes, please give lots of love to your W212.054
I can and will "poison" you to be as **** as I am for car maintenance...... soon ...ha ha ha
I ordered o2 sensors from fcpeuro yesterday (after some struggling to get my payment approved, had to call my bank to whitelist fcpeuro/paypal). Now the looooong wait of 2 weeks
However, after its been a while not checking my LTFT, I'm surprised it creeps back up again . So all those parts replacements did little to improve my LTFT. I really need to find a shop which can do smoke test here.
In the mean time I got this cheap OBD2 display so I can closely monitor the car condition, surprisingly for about 100 USD it does display a lot of things.
You must remember that the 02 sensor of yours the front one is reading false RICH, if we compared it to the emission test Lambda sensor.
So, be patient and don't worry about the current fuel trim, as the sensor which decides the fuel trim is kinda "drunk" now
How is your PCV crankcase vent condition:
nearly new or
way too old ?
It can become a significant intake leak with old cover seal combined with pistons blow-by pressure.
Your engine being lean is hotter than normal and slow poke... take it easy with "Italian RPM's" until it gets back near tuned.
PCV system was just replaced a week ago or so, everything listed in this https://www.fcpeuro.com/products/mer...kit-oem-515810 . Initially there was an improvement (LTFT goes down to 5% or so) or maybe that just LTFT being reset because when doing the work the battery was disconnected. There was also problem with intake manifold (replaced the actuators), while at it replacing the intake manifold gaskets, injector seals, injectors cleaned and calibrated. Fuel filter also replaced.
No noticeable problem on the engine, everything run smooth, power also nice and responsive, xentry / scanner did not shows any errors. Just failed emission tests
I'm starting to think it is not vacuum leak issue, because when stationary I rev the engine to 3000rpm for a minute it did not bring LTFT down (and STFT stays at 0%). But somehow when driving in good traffic highway (not a lot of stop and go) it does bring LTFT down a bit)
Cold start also bring STFT to -10% (maybe its because still open loop)? when its warmed up STFT goes back to 0%.
Originally Posted by S-Prihadi
Tesna,
You must remember that the 02 sensor of yours the front one is reading false RICH, if we compared it to the emission test Lambda sensor.
So, be patient and don't worry about the current fuel trim, as the sensor which decides the fuel trim is kinda "drunk" now
yeah O2 sensors replacement is my last hope lol. I hope it will fix my fuel trims. If o2 sensors did not fix my issue I might going crazy . At least the car is refreshed a bit (a lot of parts replacement)
Came across this thread searching for O2 sensor info. I just received a new Bosch O2 sensor from FCP yesterday. I have the M272.948 engine. I had taken my car to a shop to have the exhaust manifold replaced and they ended up calling saying they cant do it so I got the car back. Now the check engine light was, which it wasnt previously. I scanned the car and came up with 0443 "output for heater of o2 sensor 1 bank 1 has a fault". It appears while they had the car they must have removed the right side cat and im thinking they put them back wrong. I cant easily get the sensors out so I unhooked them at the harness and it looks like oxygen sensor 0035427018 is installed in the bottom hole, and the 0045420818 is installed in the top hole.
The only numbers I can see is on the connector, 1928404682 so I found the same on FCP and thats what I ordered. When it came in I saw the number on the box and figured they sent me the wrong part, but it seems to be the same one after seeing the number on the connector.
I have a question since I know nothing about O2 sensors and i'm a bit confused, am I correct that this O2 sensor should be installed in the top hole, and NOT installed in the bottom hole of the section of exhaust pipe?
And if so and the sensors have been switched will that cause the check engine light? I ask because when I look at the sensor installed in the car the metal part at the top looks bent, like maybe they jammed the O2 socket on and damaged it, which is why I ordered the new sensor. The old sensor looks like it was made in 09 so im def replacing it, just curious if you think its probably broken, or the check engine light is on due to its location?
For the PCV I was worried about oil in the intake so bought the new passenger breather cover and drip pan, but when removing it appeared the old parts were fine especially the drip pan. For the drivers side i removed the cover and wanted to see how it worked, took it apart to see theres no moving parts or anything that looks like it can wear. I just cleaned it up with soap and water and re-installed it, guess I got lucky the gasket was still good and no leaks still.
Tim wrote in blue : I cant easily get the sensors out so I unhooked them at the harness and it looks like oxygen sensor 0035427018 ( wide band ) is installed in the bottom hole, and the 0045420818 ( narrow band ) is installed in the top hole.
That is wrong installation.
Wide band should be the top or upstream and thus the narrow band is always downstream or bottom one.
Easy to ID the 02 sensor by the wire or PIN count on .
Narrow Band uses 4 pins. The Bosch P/N is 02588006749 . Family is 16749 and this is on the box and not on the metal body.
Wide Band uses 5 to 6 pins. The Bosch P/N is 0258017016 on the metal body, same as your photo. Family is 17016
The P/N on the connector, that is connector own P/N.
Technically those 2 connectors can not be connected to the wrong sensors due to their difference in pin number and shape.
Tim wrote in blue : And if so and the sensors have been switched will that cause the check engine light? ( 0443 "output for heater of o2 sensor 1 bank 1 has a fault".)
Possible, but I am more worried that the connector pin may get damaged, could be the female side or male side of the pin.
The working room to connect the sensor' connector to car side receiving connector.... if for my car and most V6 & V8 MB is a nightmare space wise, thus pin getting damaged can always happen.
today is a hot day (I seldom use the car during the day, usually on the morning and the evening). The LTFT got even worse (first time I saw above 12%!) Maybe soon will throw CEL.
worst LTFT so far
Intake air temperature was 60 celcius, so I guess its normal to ECU enrich the mixture (hot air = less density?)
After I got home I hook up my launch scanner and see more details
bank 1 and bank 2 LTFT upstream lambda 1.00 downstream voltage
Is the downstream voltage reading rich? isn't should be at 0.5v for lambda = 1? if that the case the upstream is reading false lean hence dumping more fuel, I dunno . This drive me nuts Can't wait for my new lambda sensors to arrive from fcpeuro
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Less dense air should require less fuel, not more. Downstream O2 sensor measures the effectiveness of the Cat. As a test, I would get an O2 sensor offset to see if the measurements change. I don't know if they are illegal in your country, but I know Amazon stopped selling them. However, I can still get them on Temu or AliExpress.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
If the Cats have failed, this will move the sensors out of the exhaust stream and should remove any DTCs. If that happens, you know the problem is with the Cat and not the O2 sensor. You may have to search for "O2 bung extension" or "Oxygen sensor spacer" on AliExpress.
Tim: I wonder how they even managed to connect the wrong sensors because the harnesses connectors do not match.
Upstream is Lambda
Downstream is O2
Don't let this shop near your car again.
The sensors are connected properly, they are screwed into the wrong holes. I took it there to have the passenger exhaust manifold replaced. From what I can tell it appears they had removed that section of exhaust pipe from the car, and instead of disconnecting the connectors they instead unscrewed them from the pipe, they just put them back in the wrong holes. It didnt look like they even touched the connectors, Im assuming they probably couldnt figure out how to unclip them from the brackets.
I totally regret trusting that shop to touch my car, they told me they worked on Mercedes before and even did an exhaust manifold on the m272 engine. Valuable lesson learned. Thankfully they gave up after only removing the exhaust pipe so they didnt do too much damage. I plan on leaving them a long detailed review once I get this mess all squared away, people should really be warned about that place.
Thankfully I stumbled upon this thread where im learning alot about the sensors so I can fix it myself. Just have to figure out how to get the sensors out.
However, it is a low resolution sensor when it comes to how exactly rich is a 650mV ?
Also since CAT has oxygen storage capacity, voltage swing is what we want to see from rear 02 sensor to determine its proper working or see a real stuck high voltage ( example 800 Mv )
or stuck low voltage ( example 250 mV) as "bad".
Simple explanation is : rear o2 sensor after CAT reading is not instant like front wide band sensor without a CAT.
That is why graphing the rear o2 sensor is required or watch its action when you do a few fast throttle up a few times in neutral for say 15 seconds.
We CAN'T just use 1 second view of rear o2 sensor voltage.
Google this : catalyst oxygen storage capacity
The ECM while is precise, it will do slight rich and slight poor as its adjustment method to achieve the proper Lambda 1.0 , because an engine is so dynamic while in use, hitting Lambda 1.0 all the time is not possible.
This rich-poor very mild swing is also how ECM can see CAT performance.
Here is an older test log, a car being stationary and I was monitoring oil pressure. The 02 sensors all 4 were old ones, original to the car.
ABOVE : See data points 3,800 to 4,200 which is idling only, see the Bank 2 red-sensor is lazy to swing, while the Bank 1 green-sensor is swinging above and under 450mV.
................ See data points 3,200 to 3,600 where I peg the throttle to 4,000 RPM, see how active the Bank 1 green-sensor swing above(rich) and under(lean) 450mV.
BELOW : Temperature of front Lambda sensor 1 both banks are so similar, you see only the red line , the blue is hidden under the red. Green is the Bank 1 downstream sensor.
OBD2 standard uniquely does not have Bank 2 sensor 2/downstream data PID, hence this 3 data PID only and not 4 for us a V6 or V8 or V12 twin exhaust and 4 of sensors system.
.
BELOW : Fuel Loop #4 is Open Loop at high throttle or decel. Loop #2 is Closed Loop.
While I did not play with throttle-up, from start of COLD engine to 1,200 ish data points or 4th minutes , we can see voltage swing at 800ish data point or 2.6th minutes.
Best activity of CAT ( also seen as o2 voltage swing ) is when at 500C and up, approx at 1900 ish data points.
The sensors are connected properly, they are screwed into the wrong holes. I took it there to have the passenger exhaust manifold replaced. From what I can tell it appears they had removed that section of exhaust pipe from the car, and instead of disconnecting the connectors they instead unscrewed them from the pipe, they just put them back in the wrong holes. It didnt look like they even touched the connectors, Im assuming they probably couldnt figure out how to unclip them from the brackets.
I totally regret trusting that shop to touch my car, they told me they worked on Mercedes before and even did an exhaust manifold on the m272 engine. Valuable lesson learned. Thankfully they gave up after only removing the exhaust pipe so they didnt do too much damage. I plan on leaving them a long detailed review once I get this mess all squared away, people should really be warned about that place.
Thankfully I stumbled upon this thread where im learning alot about the sensors so I can fix it myself. Just have to figure out how to get the sensors out.
To spin loose an oxygen sensor with at least 4 working threads or 360 degrees x 4 full rotations, without first removing its connector can damage the wires from over twisting.
This is a good video on how tight working space is for accessing the o2 connectors from a member here ( he is doing engine mounts ), while his is a V8 M157 engine, more or less M272 would be at least 85% as difficult.
I have to go to my indie for o2 sensor work, my fingers too fat to access the connector but my indie has 1 guy with small slim hand and he can do wonders....
Also, me at 57 year old now, me fingers lost its sensitivity some years ago and also its power. So sad.
I got Carpal Tunnel on both hands that is why, its bi-etch to have this wear-n-tear on the hands.........
.
Last edited by S-Prihadi; 09-21-2024 at 10:52 AM.
Reason: add info
09-09-2024, 09:23 PM
Yes, please give lots of love to your W212.054 
. So all those parts replacements did little to improve my LTFT. I really need to find a shop which can do smoke test here.
. At least the car is refreshed a bit (a lot of parts replacement)
