The option of fuel quantity on mine is, basic, slightly enrich, enrich then lean out.

The fuel door on mine also says 95 recommended with 91 minimum. I tried to use ron92 before but I can hear slight knocking if I quickly push down the gas hard (I wonder why the timing is not retarded). I tried ron95 also no knock were heard.

Regarding the octane setting on launch I assume it was AKI numbers as used in US lol idk. Because I m assuming no way mercedes has the option to actually use 89 ron 😅

if using AKi my assumption are
89 AKI = 91 ron
91 AKI = 95 ron
93 AKI = 98 ron
​​​​​​
or my assumption is wrong lol

https://mbworld.org/forums/45237-post7.html

Possible to check if the timing has advance or retard from launch scanner?

 

Interesting. My car does not give me the option of altering fuel enrichment. Our ECM designations are the same, MED177V6LA.



In the US, the fuel door info states minimum octane rating of 91, or approximately 95 RON.

 

I haven't inspect the old filter, I did bring it back home, perhaps later in the weekend if I have time I will try to disassemble it. However the tank seems clean from quick observation (scared to took phoots afraid it will cause a spark lol)

As the fuel quantity I just changed it back from lean out to basic as I feel on my butt dyno the engine not as responsive as before and power seems to be decreased (according to my butt dyno). Fuel consumption figures also dropped down on my usual route. You should do emission test, its only 150k IDR. I never knew my car had problem until I did not pass the test.

Can you check the part no of my o2 sensors? my vin is MHL212054AJ001238 . I think I'll replace it soon

 

Are you saying that the car felt stronger with a leaner setting? Running a little lean can produce more power, but it is also more danger to the engine, especially on a turbo car.

 

no its the other way around for me. on leaner setting the car feels not as responsive and reduced power (according to my butt dyno). Fuel consumption figures also worse on my usual route on leaner setting. That's why I changed it back to basic setting on fuel quantity (but still left the octane at 93 for now)

 

This is what the EPC has for your O2 sensors:

 

In Xentry since Indonesian market Mercedes is a European spec, the ECM data speak of RON and not USA AKI.




USA is a unique market and it is different due to much tighter emission regulation.



Jetta,
Thanks for the Xentry screen capture of your M276.8 fuel enrichment setting being "locked".... poor soul you



Tesna asked : Possible to check if the timing has advance or retard from launch scanner?
Difficult to see true value, we can see variable value, because this timing is Ignition timing and very dynamic on what engine load, RPM, and throttle input at that point in time and many other factors,
including barometric pressure when at high altitude driving.

I can show you a sample of mine, it is available in OBD2 mode .



.






Highest Ignition Timing Advance is 39 degrees.

.



.




Here is a good read. Porsche owner from Sydney comparing ignition timing retarded by the computer when 95 RON used instead of 98 RON ( Not USA AKI ).
I do not know if the Porsche has fuel quality sensor or not.
https://rennlist.com/forums/996-foru...8ron-fuel.html

Good read on Ignition Timing : https://www.uti.edu/blog/automotive/ignition-timing


------------

Knock sensor is not a solution for lower than recommended octane / RON of a fuel for an engine. It is a safety device but it has to hear the knock first,
meaning pre-ignition already happened, and then it tells ECM to retard timing. So damage will occur when this happen too often.


--------------

I will do an emission test for fun 2 more weeks.
Nawilis Tanah Abang has one. Me in Jakarta Barat, so they are close to me. I asked for its model. See below


https://www.brainbee.mahle.com/brain...ssion/ags-688/


--------------


Find attached a good read of a local University doing emission test. In English.
Yours and my engine should have HC well under 50 PPM at idle or we should be ashamed

Dang, these 2 baby engines still new I know, no higher than 14 PPM of HC.

 

@S-Prihadi I'm wondering if Injector injection quantity adjustment would have the same effect as Correction programming of fuel quantity? Seems like it might. I could check the next time I hook up my SDS.

 

@S-Prihadi ok I will change the timing to basic and will see at least the fuel consumption figures. thanks also for a lot of informative info, will took time to read it


This morning I drove the car and see the long term fuel trim decreased in value when driving in good traffic at about 10 minutes or so with minimum stop (it was 9% and 5 %). However when stuck in traffic for 20 minutes it incresed again to 10% and 6%. The short fuel trim still at near 0%. I guess 0% is based on long term fuel trim, the most important thing is that one.






I guess I have small vacuum leak somewhere, since it affected the most when idling. When the car in the workshop it was inspected for any leaks and the workshop found none.

Any idea what usually caused vacuum leaks on m272 engine? Will bring the car to another local indie mb specialist soon, I really want to get this fixed 😅

 

Find a shop that will do a smoke test to check for vacuum leaks.

Or you can get your own smoke generator. There are YouTube videos on how to use one, I'm sure. Here are just a few inexpensive ones on Amazon. You can also try eBay.

 

well well, the problem has been found (I hope) . It appears I need to replace the tumble flap (is this the intake manifold?)

why it does not show on my launch scanner tho when I scanned it last week i am not sure. When the mechanic have a quick look at the engine bay, he immediately noticed hey your tumble flap is at wrong position, when idling the position should not be there

and xentry confirmed it

 

double post

 

Jet,
Injector injection quantity adjustment is when you have new injectors and need to tell ECM its fuel adjustment value. 5 or 7 digits thingy or using barcode.

.

 

If car is still having this STORED and CURRENT DTCs not cleared yet, you try using Launch to confirm if it can see those DTC or not.
Of course Xentry is the best for MB, that we can not argue. However 3rd party scanner sometimes can go kinda banana with new software updates.
I seen my Autel and Launch gone thru updates like 5 MB software each at least and sometime they get worse and not better and we hope newer software to be available to correct it,
as we can not go back to older SW version.

I hope the tumble flap issue is not anything broken INSIDE it.
I did warn you in post #10 about this infamous intake manifold

Here is a good watch :

The M272 engine document tells a lot of how this intake manifold airway management works.
Basically it does 2 things :
01. It makes the intake breathing air travel longer or shorter distance, depending on load.
02. It also has swirl flap like M271.8 EVO engine.

Group 1 and 2 components can break at the link in the exterior and interior side.
Group 3 are electrical solenoid to control the vacuum to group 4 components.
Group 4 are vacuum actuators

 

This is M272 intake manifold, when and if the vacuum electric solenoid is the issue.
So this is electrical and not mechanical. Hope that is is your issue, it is cheaper this one


.

 

Well, today is a loooooong day.

I did not try to rescan again using launch as I ordered them to fix it immediately (battery was immediately disconnected). The part is cheap (IDR 750K!!) but the labor is just as much as the part, they have the broken part in stock since it is very COMMON problem found in M272.

Since I complaining about the vacuum leak they also replaced: intake gaskets (both bank), injector seals (12 of them) and clean most part of the engine which usually leaks oils/air (so when it leaks it can be easily noticeable hopefully)

While at it they found my engine mounts is bad (why I did not notice it ?!?! ) so I replace all of them (including the transmission mount). The accessory belt also replaced


the broken plastic connector

cleaned and replaced. I can see the flaps moving (which indicates the inside is fine right?





It seems mine is mechanical, after its replaced the error codes does not shows up anymore.

HOWEVER, when I drove the car back home (1.5 hour trip!!!) 60km distance, with mixed some good and really bad traffic. the long term fuel trims does not improve it should be improved right? 1.5 hour is driving should be enough to update the fuel trim right? Engine responsiveness, power, and smoothness also feels the same as before (no noticeable issue whatsoever) So the hunt for vacuum leaks does not end yet....



I did not feel the improvement after replacing the engine mount also (before replacement also no vibration felt) Howeever the old mount has noticeable difference in height compared to new one

 

So your intake manifold is broken at the common break point, the big vacuum actuator to the twin arm for swirl flap....right ?
I labeled that as component group 1, the 1C.



.



That thing controls the swirl flap for faster engine warm up and other certain operating condition.


So that misfire ECM recorded and then became STORED, that is probably during warm up process.



If Components 2A and 2B are the broken ones, that can make bad misfire and poor power.




------------------


Don't expect our engine in Jakarta traffic to have long term fuel trim to be super low like 3%, usually it is not the case.
Stop and go driving has lots of acceleration , that means power demand is often albeit not high power. To accelerate the engine need to be a bit rich.
If in highway and flat one, under cruise control, very constant driving, that is the best fuel trim one can ever get and that don't happen in Jakarta city ....
Yes, LTFT 10% is rather high....if at all the time at 10%.
But come to think of it, Short Term being 0% all the time unless idling..... is something which should not be, if you are able to log it say for 3 minutes while car is moving.


Here is a short city traffic run, 32 minutes while in Surabaya. 5Hz data log.





Short term fuel trim, very dynamic and is following car movement/acceleration or throttle




.

It will be good to see LTFT on a graph like above, as it always changes according to your driving condition.
As you can see, 32 minutes of driving, how many times the LTFT is being adjusted ..... many many times. Its like every 1-2 minutes it adapts.
If you see only 1 second worth, it could be at -4% or -10% ...











The front wide band o2 sensor ( lambda ) is the one telling ECM how much fuel to cut or add from target 1.000 lambda.
So this is why front lambda o2 sensor must be kept healthy as it is the only sensor which can tell ECM actual proper air to fuel ratio.

On the subject of your PM tonight.
Where the mechanic recommends to wait for 02 sensors DTC before replacing them.
Where supposedly if o2 sensor went bad , fuel trim mainly will go negative and not positive. ( note : negative fuel trim means RICH )

Xentry will only give DTC when heater circuit in 02 goes bad or sensor has really gone bad in some ways detectable, but Xentry can not detect if o2 sensor becomes less accurate or rather slow.
The rear o2 sensor under OBD2 Mode 6 has monitoring feature called Rich To Lean sensor switch time ( calculated ).

Here is an example of a front wide band sensor ( lambda ) from a BMW 330i which reported false RICH, as such it causes the engine to be LEAN.


This N52 engine BWM on the video by looks of the signal from the lambda sensor value, it is Bosch LSU 4.9 family, like on my M276.8
It is using Bosch LSU 4.9 https://bimmerprofs.com/substitution-lambda-probes/




So, a wide band o2 sensor if defective can false report RICH or LEAN I am sure. It just so happen this BMW N52 330i front wide band o2 sensor is REALLY bad false RICH, as such misfire
and LEAN code DTC pops out all the time.

I am sure your front wide band 02 sensor or rear narrow band is not defective, probably slow.

If you can graph the front wide band Lambda value while in normal city driving, you can see how active it is. if it is lazy, that is a problem.
You should also see how active is the rear narrow band 02 sensor voltage. It should go up and down like yoyo, that is a good one. This is how CAT works, it need the Lean-Rich swing.






Take this condition of your engine after 14 years old as a blessing. This is a learning process.


------------------

To test weak but not terrible engine mount.

Idle, in gear D or R vs Neutral and run the AC system.
Sense the vibration on the steering wheel....very mild extra vibration when tranny engaged to D or R, brake is to be applied all the time.

Don't wait for crazy vibration, that is already too weak an engine mount. FYI, I replace my engine mount per 20,000 - 25,000 KM.... I am that sensitive to changes in vibration and I am a heavy throttle foot.
Now my engine and tranny mounts are 3rd set already, counting 1st one original in the car when assembled in 2014.

Read here for engine mounts : https://mbworld.org/forums/e-class-w...tear-down.html


Here is my 2nd engine mounts at 18,000KM old, vs new one.

All you need to see its its "sinking depth under load".





NO LOAD. Yes, this engine mount is still useable to 99% of drivers for another 20,000KM, but I don't like it. I can feel the extra minor vibrations already.





Here is my engine & tranny mounts change history. Today my car is at near 42,000 KM.




Your belt changed, did you check the tensioner and the 2 pulleys ?
Serpentine belt is 5 years for me, regardless of mileage, surely under 25,000KM per 5 years anyway.
I have replaced my tensioner and pulley, not because it went bad.... it was not perfect like new anymore, I done too much redline RPM I guess.... LOL
You can read here : https://mbworld.org/forums/e-class-w...ew-vs-old.html


.

 

Yes the one broke was the group 1 actuation mechanism, and it seems it broke just very recently since the broken plastic part is not covered with dust/oils.

Possible to do data logging with launch? I did saw record button but I dunno where to retrieve it lol. I will look at it maybe this weekend.

As the o2 sensors, perhaps I'll replace at least the front two sensors

My old engine mount is 14 years old LMAO, the mechanic says oh man the bolt is very hard to open, it seems this is the first replacement after 14 years lol. That's why when the mechanic said need to be replaced I immediately approved it. The old one is very sagging so bad.

The belt, I did ask the mechanic why he did not tell me to replace the tensioner and the pulleys, he said no need, no play observed and not making any strange noises. I was like oh ok. Btw, the old belt does not have any sign of cracking yet, perhaps previous owner has replaced it sometime in the past (maybe)

 

I got time today, so I went for Emission Test.

First I wanted to see the machine free air ( ambient ) air reading accuracy.
I am **** when it comes to gas sensors, as I do own 02, CO and CO2 sensors for my dive compressor use. High resolution ones. I never owned an HC sensor
Gas sensors need to be renewed like per 3 years and best calibrated per 3 months, not once per year. Buying the calibration gas is a pain.






Unit spec





Bank 1 or Left side exhaust system. CORRECTION, Bank 1 is RIGHT side exhaust dugghh !!!
My photo vs press to Print is not exactly the same time. So the numbers a bit different.



.
CORRECTION, Bank 2 is LEFT side exhaust dugghh !!! The Left and Right position is the correct one. The Bank ID is the typo


All good for my engine


Test Cert, valid 1 year.






I have not measured a Euro 4 car CO level in exhaust gas before.
I have measured portable 6.5HP Honda gasoline engine for my dive compressor. Peaked at 500 PPM , but my sensor was 0-500 PPM class for breathing air safety.
So my car C0 ( carbon monoxide ) at tail pipe is only 200 PPM ( 0.02% ), assuming the CO sensor is still accurate to that low.



Now our emission test compared. Which exhaust pipe did the tester use ? Left or Rights side ? I think it is Right Side , because easier for techy to get into our RHD car .

.



Looking at the OTC StarGas 898 emission test machine result for the E300, the Lambda at 1.060 and the oxygen level at 1.27% indicates the Lambda sensor used by the test machine is accurate.

The E300 long term fuel trim is positive Bank 1 +10% and Bank 2 +6%, while the emission test Lambda sensor also indicated LEAN at Lambda 1.060 or AFR 15.8

I am assuming this is idling and engine has reached proper operating temperature....yes ?
If above is the E300 typical lambda reading while at idle and proper operating temperature , this is then false RICH reading.




Lambda to AFR conversion table





Spec of the OTC StarGas 898. It has higher resolution for CO gas.





All ECM will target Lamda to as close as possible to 1.000 or AFR 14.7. So your wide band front 02 sensor seems to be drifting towards false rich. 14 years is good service life already.


From : https://edisciplinas.usp.br/pluginfi...ambda_poli.pdf This ETAS is owned by Bosch.


So, me replacing my front LSU 4.9 and the rear narrow band ones at 10 years old is a good move. Its still good enough but not SUPER FAST enough probably.

If you will replace the o2 sensors, replace all 4 o2 sensors, don't just replace 2 front ones.


.....

 

@S-Prihadi very good analysis and detective work! wow your car emission results is very good!

The technician took the test on the driver side only (I'm not sure is that left or right lol, from the backside it's the right one). From previous diagram you sent that is the bank 1 (the one with higher fuel trim), However, if the lambda detected lean so the ECU is correct to add fuel into bank 1 then? and that emission passed only if I set the fuel setting to LEAN OUT mixture. If I set to basic value I did not pass inspection. With mixture set to basic value, the lambda detected by emission machine is 1.056. (from lean out one 1.060) not much but enough to bring down HC to get it to pass emission test.

If I replace the o2 sensors to get more accurate lambda, my guess my actual mixture will be even richer isn't? or my thinking got the other way around

below is result of last year inspection. I cant believe this year suddenly got so bad

 

scoured all over the internet what caused positive long term fuel trims, and have found someone has similar problem as mine. Not same vehicle, even not the same brand. He did smoke test, clean injectors, replaced maf, upstream o2 sensors etc without any luck, until someone recommend to also change downstream o2 sensors, now its back to spec. The thread: https://www.trailvoy.com/threads/p01...rating.216054/

Going to replace all 4 next week! I was afraid if I did not fix the leak it will damage the new o2 sensors. lets hope this will also fix mine.

 

So the emission test probe is at the Bank 1, RIGHT side exhaust system.


Next time get them to test both exhaust, because our V-6 is like 2 of 3 cylinders engines.
So we need to know both exhaust/banks value. You use the "cleaner" value one for the Emission Certificate

If only you have test result for LEFT exhaust ( Bank 2 ) too, it will be better for us troubleshooting it.
Let's work with what data you have in hand.

Since your LTFT is not in a graph form, we wont know the trend but assuming both ECM data and Emission test data is the same engine idling period,
your ECM Lambda Sensor at right side bank 1 should be showing closer to 1.06 and not too far off like 1.02.
Most likely at during acceleration the ECM lambda sensor right side Bank 1 reads even leaner or drifted much more, hence +10% LT fuel trim is what you are seeing.

One thing we need to remember, priority one by engine designer and car brand and the software programmer is : EMISSION and fuel economy. Emission is King #1.
Whatever programming made to our ECM and what hardware installed, it is all about emission and not performance.

Rear o2 sensor is there for CAT only, and since CAT is emission device, at times it can have higher priority than front o2 sensor, depending on how the engine management software is
targeted to be at certain scenario. When 2 data sources produce conflicting result based on the same gas measured , which the front vs the rear o2 sensor in this case, emission result could be then priority 1.
So in the case of the TrailVoy forum , it seems the ECM placed CAT performance aka emission as priority 1.
2007 GMC Envoy being the car in their discussion, I check the front is a narrow band, 4 wires Bosch 15131 family. https://www.autozone.com/engine-mana...gmc/envoy/2007
If front is narrow band, guaranteed the rear is also a narrow band. Too bad the owner did not graph both the front and rear oxygen sensors voltages.
But it was in 2009 and OBD2 dongle/display is not as cheap and plenty or as good as today or 3-4 years ago.

--------------------------------


Today on the way to Pantai Mutiara while doing 60+ seconds idling at traffic light stop near Pluit Junction.


Snap shot at that point in time 5:18PM and approx 75% of total journey of 8.8 KM.


So replace all 4 o2 sensors and then do again emission test, but this time test both exhaust/banks.
If the emission test workshop is close to your house, make sure you engine oil gets hot enough to evaporate piston blow-by dirty gas and moisture.
30 minutes drive is a good minimum.

Sometime contamination can also accelerate defects to o2 sensors, example engine coolant from very minor leak at cylinder head gasket coolant path into combustion chamber.
Engine oil lab test can show if indeed such contamination did occur.
Even unsuitable sealant I read can contaminate o2 sensor.
https://www.walkerproducts.com/commo...or-conditions/

Me waiting for your good news.....

 

@S-Prihadi today I consult with another local indie (first time visit, just curious what they know about what possible vacuum leak causes). I still believe there's little vacuum leak somewhere. Then they mention about Crankcase breather, as they check on the tube there's oil in it. It should be filtered out. Then I remember fcp repair kit https://www.fcpeuro.com/products/mer...kit-oem-515810 . They said to only replace oil separator cover only (A272010063) no need to waste on unbroken parts. I said, hey its 14 years old car, I hate going back and forth to the workshop. Just quote me the list I requested:

1. Crankcase Oil Separator Cover - A272010063
2. Expansion Plug - A0009986590
3. Oil Separator - A2720160134
4. Crankcase Oil Separator Drip Pan - A2730100162
5. Crankcase Full Load Breather Hose - A2720180682
6. Crankcase Breather Hose - A2720181382
7. Air Intake Seal - A2720940080

However some of the part they don't have original mercedes part, one of them is by febi. I insist to get original MB parts. However, they said even MB branded one on the market is most probably fake. Better to get OEM brand like febi, bosch, lemforder etc, or if really want to get original parts, go to MB dealership. Well, I'm not surprised, this is Indonesia. This makes sense why most local indies insist not replacing components unless detected by xentry, if ain't broke don't fix it, most likely the replacement will not have the same quality.

For crank case breather kit I think its ok to use OEM parts, what do you think? for oxygen/lambda sensors I think I need to order from fcpeuro lol, afraid to get fake parts if order locally.

 

I am out of town, so let me work from my memory and use M276 as baseline, which your M272 should be similar in all aspect of emisssion devices.

Other "air" consumed by your engine , aside from the one passing thru the MAF at/close to throttle body, are :

01. PCV system is sucking in piston blow-by air from crankcase.

02. There is also a gasoline fumes ( fuel vapor) system suction by engine called "purge valve" or EVAP system.
I don't know the exact plumbing details for M272 or M276 3.5NA fuel vapor, but I know well my M276.8 3.0 Turbo fuel purge.
If the hose is cracked, you will get lots of ambient/fresh air into the engine after the MAF, as such the MAF won't read this alien air.
Must test the soleoid valve, will it close a a 100% and air-tight ? Will it operate/open ? The baby launch can activate it.

03. Actual breathing air of engine via air filter and all the plastic air box or hoses yada yada toward throttle body and into intake manifold.

----------------------------

04. Secondary air injection system.
This one I am blind , no experience with this stuff, but I know this is emmission device too.
This extra air goes to the exhaust, when needed.
https://www.ms-motorservice.com/int/...y-air-pump-340
Looking at the explanation, this I believe can also contribute to lean reading of lambda sensor when and if air injection happened outside the required parameter or if there
is a leak at the air injection point at the exahust side.
Dang, I never realized M272 actually has this system till I saw the pump.
See here :

Parts : https://webautocats.com/epc/mercedes...asis=212054D02
.



EVAP system, M272. Indonesian market MB engine EVAP system lacks of pressure sensor at the charcoal cannister, so we won't be able to get DTC from an EVAP leak like US market ones.
While this video below is of a W204, the engine is M272.

Vacuum leak means alien un-registered air, from a leak , but after the MAF sensor.
M272 uses a stand alone vacuum pump for vacuum works, example the brake booster and the vacuum actuators 3 of them at your intake manifold.
So do not get confused by "vacuum leak" for engine breathing vs vacuum pump leaking from cracked hoses.

A. Vacuum leak integrity , all seals/o-ring after throttle body
A1 - I believe you have replaced gasket #40 and 2 of #120 right ? https://webautocats.com/epc/mercedes...asis=212054D02

A2 - All seals before throttle body is for making sure air is clean and if air filter housing has pressure sensor, those seals are important to not leak, as sensor is there to sense differential air reading within the air filter housing. I do not know if M272 has such pressure sensors ? My engine has 2, one at each filter housing CLEAN air side.


----------------------

MB official dealers like Mercindo at Toped I gave you the links, they will not sell you fake/counterfeit parts.

There is one other seller in Toped, which sell aftermarket parts for MB and also genuine one, when and if they stated GENUINE / ORIGINAL
Example the PCV oil separator https://www.tokopedia.com/pbauto/sep...-mercedes-benz


Best peace of mind go to nearest MB official dealer to your home or office and order there.
Me always order from Dipo Motor pluit via my indie, so that my indie can make say 10% on it.

How to use QR code and barcode of MB label to check for fake/counterfeit parts. Quite foolproof, but not as good as Mobil 1 fake oil checker Apps.
https://mbworld.org/forums/e-class-w...tensioner.html

--------------------

FCP Euro would be a good source for the 4 o2 sensors, Bosch ones and not Bosch-MB labeled.

 

Secondary air injection is used during cold starts to raise the cat temperature quickly. After a few seconds, the secondary air pump should not need to run again until the cat cools down.