S-Prihadi

Mine is M276 3.0TT, very much probably the same with M276 3.5 NA




2,000 RPM the oil pressure is already sweet with valve OFF. 40 psi already
35 psi if at 1,500 RPM, not bad.




DTC, sure. ECM will issue the warning when scanned but no check engine light as per stationary test of +-20 minutes with 3 engine cycle ON-OFF.

S-Prihadi

I have not scoped the 2 stage oil valve control signal yet, but seeing its not-so-easy oil pressure regulation zone, it must be PWM type of regulation. Not a simple ON-OFF at 3,500 RPM only.




If not regulated by oil control valve, 30 psi at 1,000 RPM is what the oil pump can do.




At idle of 600 RPM, if oil valve is active and allow less oil towards oil galleries for moving parts, it is actuall 3.5 psi average better oil pressure than when oil valve by-passed ( OFF)

CaliBenzDriver

Thank you Surya for showing us these real data vs. MB design documents.
Now we can see live numbers and what condition makes "normal pressure vs. half pressure".
​​​
First thing that jumped at me is this is not fail safe...
> The valve needs to be actuated to get the normal pump pressure.
> At rest the pressure bleeding valve delivers 17Psi at idle and a maximum of 30Psi (2Bar) with RPM.
> When anything goes bad with the valve, the lubrication is stuck limited. Pressure Faults are not indicated by CEL but a DTC entry in ECU list. You can unknowingly red line your TT stuck on low pressure until something quits

overall lub description

Two stages :
This is not a special unseen oil pump that delivers high pressure! It's just a regular pump with a calibrated bleed valve controlled by the ECU.
The engine is either lubricated by a limited half pressure (30psi) or by Normal pressure (60psi).


the nugget section: piston spray disabled

The engine pistons don't always get sprayed by oil... Nothing is mentioned about how this is all controlled.

I wish MB would say what modifications if any were done to M276/8 engine family to help it operate under low lubrication without piston rings and bearings wear.


PWM regulated vs. On/Off:

• It seems they are only going after basic two pressure steps: on/off
• switched at fixed RPM
• based on ECU engine needs assessment.

Any of this is likely to be tweaked for improvement with ECU software releases.


Disabling low pressure... SW/HW:
To enable unlimited normal lubrication the valve needs to be powered with a GND return path.
The easiest way would be to disable the feature programmatically through Xentry, plan-B is the following quick hardware mod.


Unlimited pressure bypass switch
> The GND signal from ECU to solenoid is interupted by a switch to GND that can enable pressure solenoid to deliver normal pressure.
> A 10kR or 4.7kR is inserted to act as dummy load so that ECU can not sense the missing solenoid load.
> ECU may possibly still flag the normal pressure when it expects a low pressure at sensor.
> We know VVT map is pressure dependant, so back and forth switching idle pressure may be flagged abnormal by VVT logic.... Retrain it.
> At least normal pressure will positively prevent chewing up the soft VVT lock pins with low pressures... good deal 👍

WHERE to install HW mod:
Near ECU or near solenoid??
> I'd say solenoid may be best because TT has ECU over engine crown and 350 has ECU over exhaust collector... different spots!
Solenoid is in same spot, provides +12 from solenoid for 4.7kR and GND from nearby engine screw.

S-Prihadi

Its a fail safe design Cali, at least the one on my engine. So a normally open so to speak.
The Valve OFF or By-passed, the top graph with higher pressure at 1,000 RPM up to 3,500 RPM is X26 no 4 connector being disconnected. That means I also lost power/control to Bank 1 turbo by-pass valve and lost power to oil level switch.

Pin 4 , LIN for alternator
Pin 7 & 8, Y130 Engine Oil Pump Valve ( 2 stage control ). Pin 7 is power source, circuit 87M2e
Pin 9 & 10, Y101/2 Bank 1 ( RIGHT SIDE ) Turbo Bypass Valve. Pin 9 is power source, circuit 87M2e
Pin 13, S43 Oil Level Switch







The only way the oil pump can stop spraying the piston underside at that 2 BAR means Valve ON state, and therefore there is an oil gallery to the piston underside being closed by this activation of this oil valve

I am sure the control for the oil valve is not a simple ON/OFF, it is PWM because of the precision of maintaining 2BAR /30PSI between 1,000 to 3,500 RPM.
I shall update tomorrow yah.

CaliBenzDriver

ok, now I am confused. At least, I believe you when you say it's fail safe if the logic is reversed 👍

This is what through me off:

On/Off : High/Low

On the left side Valve OFF: Low pressure/rpm
On the right side Valve ON : High pressure/rpm

From that I understood valve was ON at high rpm and now you're saying valve is ON at idle for low pressure. I like that better.
That sounds safer for these engines

S-Prihadi

So sorry Cali, I will make the explanation clearer.

Cable disconnected means there is no ECM command to the oil valve. The oil valve is a Normally Open one ( fail safe ) and if it is not working, oil is delivered 100% to the oil galleries of the engine moving parts, hence higher pressure when near 1,000 RPM or more.

As-is untouched is original MB set up. Depending on coolant temperature and at a mere 620 ish RPM with 55C coolant temperatute, the oil valve is already turned ON at 80% PWM duty ,
which means it will close part of the oil flow to the oil galleries and dump it back to the oil pan.
This results in oil pressure reduction towards the oil galleries of the engine at approx 27 psi average once passing 800 RPM.
At above 3,500 RPM, ECM will cut power to 10% PWM duty which is basically Valve is OFF and the oil pump will then behave like a normal non ECM regulated oil pump and pressure will hit 55 psi.

===========
NOTE : Either this oil valve works its restriction at output or suction of oil pump, I honestly do not know. Either way it can work in pressure reduction.
===========

As to why at 600-800 RPM if the oil valve is active or choking some oil path, it produce better oil pressure within that narrow RPM band compared to oil valve OFF or totall open oil path,
I think it has to do with restriction is better at low RPM. Higher pressure does not always mean higher liter per minute flow in this case. This is my guess.

According to engineering literature I read, 17 psi at idle 600-800 ish RPM if oil valve is say DEAD/not activated , it is more than enough already for the engine.
I attached a link to a nice study on 2 stage oil pump's oil pressure 101.
https://www.researchgate.net/publica...riction_Losses

I been reading quite a few studies, and some region of the engine like the valve trains will need higher Liter Per Minute oil flow than other parts, example crankshaft.


This is the video of the oil valve working normal.


I will do more research on oil pressure and volume vs RPM for engine components, before I will create a dummy load and get the oil valve out of the equation.









The Y130 oil valve connector's, it is using the heavy duty Kostal LKS 2.8mm terminals. Same as fuel computer N118.


Too bad I can not video the Banks Gauge oil pressure. It is using OBD2 port, same as my Xentry PassThru. So no-can't-do duo connection.

CaliBenzDriver

Thank you Surya, that's a lot of good news

The pressure is controlled in two stages only: either 80% or 10% duty cycle PWM - I really like your Fluke smart meter gives you both duty cycle and frequency all in a single screen.



flat max pressure...
​​​​​It's a bit strange how max pressure seems regulated (flat vs. RPM) but duty cycle remains at 10% at higher RPM....
> EDIT: the pump must have an internal pressure limiter (ball & spring).


low pressure flat
The way low pressure remains flat below 3,500. RPM helps the VVT system dial the exact position it wants 👍

The logic is fail safe: inactive valve yields high pressure.

variable lubrication vs. RPM

The white-paper from engine researchers says oil volume is only necessary at higher RPM.... in the lab or perfect world that is... else aluminum camshaft journals and leaky tensioners can deliver a slightly different experience

The oil delivery being minimized and PISTONS NOT SPRAYED below 3,500.RPM means you better drive around a bit to cool down your engine heads after TT fun driving, right?

S-Prihadi

I agree with you Cali, I am sure stable oil pressure ( high enough anyway albeit regulated ) is good for the VVT I am sure.
Good in the operational sense. I hope in the friction side of things 27 psi is good enough.
However I do wish they set set if 1,000 RPM and above at 32 psi regulated and not 27 psi like now.

Here is more test and we can learn a lot of the operational algo for the Oil Valve control.

ENGINE COLD ( 30C ). Oil Valve as is, untouched.
See how the algo does its oil valve activation, quite interesting , not a simple dumb setting, coolant temperature matters.



Engine already HOT ( 71C ). Oil Valve as is, untouched.



Engine already hot ( 80C up ). Oil valve disconnected and Dummy Load in place, 5watts x 2 bulb and a buzzer. Still short of 50 milliamps.
Oil valve is 700-750 milliamps at 80-90% duty, the 2 bulbs only average 695 milliamps. However ECM does not register fault.
See how crazy MB allows 104C coolant temp at 03:59


Cali wrote :
The oil delivery being minimized and PISTONS NOT SPRAYED below 3,500.RPM means you better drive around a bit to cool down your engine heads after TT fun driving, right?
I hate this part...why they do that... maybe its the thermal thingy, hot is good

juanmor40

"See how crazy MB allows 104C coolant temp at 03:59"
.
and, the cluster does not display continuous temperature fluctuations ; therefore, we do not see those temperature spikes which will have customers visiting the dealer too often.

CaliBenzDriver

Thank you Surya for this practical test set.

At cold start, we learned the ECU helps build up pressure by operating oil valve 10% (max output) to rebuild VVT pressure.

Later on in the 1st video during warm up cycle, the valve goes back to 10% "high pressure", WHY??
We can not measure VVT pressure but we can see VVT Solenoid activity, perhaps looking at that will provide this explanation.

> 104°C sizzling Hot:
We realized high temperature is not much of a factor to drive this valve.

While our pistons are kept unsprayed below 3,500RPM... it gives an opportunity for oil burn to accumulate at the rings until enough is collected to jam the rings in their groove.... more blow-by gases and uneven cyl. compressions.
Some people use SEAFOAM to help clean their rings loose again.

> I am more than willing to forget all the 1¢ savings in exchange for better cooling ! Question:
Could you test if VVT does tolerate to work as usual with a deactivated oil valve???

S-Prihadi

Yes, the instrument cluster coolant temperature gauge is a "cheat". I discussed this sometime ago.
https://mbworld.org/forums/e-class-w...inda-liar.html

Also M276 3.5 NA , if not my engine 3.0TT , has this Opportunistic Hot is Good coolant temperature algo.
https://mbworld.org/forums/e-class-w...ml#post8393647

S-Prihadi

I think even at 10% duty cycle, 50 milliamps power consumption, that oil valve is not 100% opened. Maybe still a super tiny resctriction on purpose.
Its not like the cooling fan where 10% duty is really OFF, fan not spinning.

Cali wrote :
Could you test if VVT does tolerate to work as usual with a deactivated oil valve???

Yes I can, but I need to see the oil pressure too and with Xentry running to see VVT commanded vs actual, I can only hook Xentry to the OBD2 port and the Banks Gauge cant be hooked up.
It will work for sure, maybe the VVT oil valve will work harder fighting the oil pressure swing. he he he he.

S-Prihadi

Now that I done Jakarta to Surabaya city drive of approx 800KM, this is a worthy log for long drive sampling after the installation of this oil pressure sensor.

So, here it is :

To update the dynamic-ness ( is there such a word ? ) of the ECM managing this LOW-HIGH oil pressure.
It is not a simple RPM based only, but driver behavior towards throttle commanded seems to be anticipated.

This is part of a log set from a 9+ hours non-stop drive, stop only for fuel + lunch and wee-wee at the toilet per 2 hours.

This is the log session file. 5 data points per second = 5Hz






Slow drive after fuel re-fill. Under 2,000 RPM


.

A bit higher RPM, 4,000 ish. P = oil pressure. T = Throttle in % . 3,400 = RPM




At approx #67 data points I kicked down 70% to 100%, by #73 data points or 1 second later engine oil already climbed up to 55 PSI and while RPM is at 3,400 , not yet above 3,500RPM its trigger point for HIGH Pressure mode.
And you guys can see at data points #151 , #211 and #253 to #319 and then #343 region the oil pressure went up, but RPM did not even go above 2,300 RPM.
So there are some anticipation or need where ECM will increase engine oil pressure not purely at 3,500+ RPM. So the oil pressure management is not that DUMB



Now I drive a little more aggressive , but not WOT yet:







Below : Now oil temperature wise. From the same 6.5 minutes portion of the log of above.
NOTE : Oil temperature is read using thermocouple at the skin of the oil pressure sensor and not a liquid bath temperature sensor like coolant temp sensor.
So, you may add 5-7C on average for oil temp reading below, to estimate actual oil liquid temperature, if the engine load suddenly increase fast.
If a nice constant load, eventually the oil pressure sensor skin temp hence the thermocouple sensor too..... will be very close to actual liquid oil temperature.
This I learn from Tranny Oil temp by car tranny computer and vs the additional thermocouple I installed on its thin skin oil pan.





So Cali, you may not benefit much killing the 2-stage oil pressure solenoid to have higher oil pressure, which is still an RPM based oil pressure due to the pump need
engine spinning faster to power it to give more oil pressure anyway. Re-visit the start of this thread.
If you spend a lot of time in bad traffic like me, hacking the 2-stage oil pressure switch is not worth it.
If yo spend a lot of time at 1,500 to 2,000 RPM, you gain approx 10-15 psi, this is worth it.

.

CaliBenzDriver

Thank you MS for the great dataset: Yum-yum.
I totally appreciate the efforts necessary to capture meaningful data and plot them in understandable charts.

Let me look over the data - See ++++

I think this may be a good time for a Vediamo procedure to boost pressure back to normal above 1000Rpm.


An engine that can vaporise burned oil by the quarts does not need less oil circulation over the super heated pistons.
​​​​​​
This valve is both a troublemaker and an opportunity to fix it.

As soon as this thing fails, engine is RIP... No, thank you!

Burnt oil is my personal cue to act. I don't need a swamp intake to coat everything all the way :

• plenum oil swamp
• intake valves
• pistons carbon deposit
• (plugs.... 50kMi)
• upstream lambda
• cat converters efficiency
• downstream O2 efficiency

Above says to lower level of oil vapor.

Now we have engines that can burn oil on demand .


+++++++++ later :
Great realife dataset shows rationship between Rpm and oil pressure vs. pump pressure control valve.

Pump circulate oil all around the engine conduits all the way to HPFP roller last to be served left over pressure.

The ghosts in the room not doken about are the hot pistons coolers.
When pressure is below 26psi ball-on-spring close piston squirters: no piston cooling. Not cooking pistons and burning oil on overheated pistons is my focus.


low base pressure while actively driving 🙄
That's a great chart that speaks loudly.
Engine is doing normal driving above idle
Pressure is limited so often it looks like the average or 50% of the time not cooling pistons.


normal piston squirting 30psi right from 1000Rpm 👍
Great simplicity for good cooling.


low pressure (no squirting) until 3500Rpm
Hot pistons burning oil when pressure available, yes?


We are both partly in agreement:
"So Cali, you may not benefit much killing the 2-stage oil pressure solenoid to have higher oil pressure, which is still an RPM based oil pressure due to the pump need
engine spinning faster to power it to give more oil pressure anyway. Re-visit the start of this thread.

If you spend a lot of time in bad traffic like me, hacking the 2-stage oil pressure switch is not worth it.
If yo spend a lot of time at 1,500 to 2,000 RPM, you gain approx 10-15 psi, this is worth it"

- We agree the idle pressure is minimal and does not cool pistons. There are limited efforts and friction at idle, so it's ok with already cooled pistons.

- Where we don't agree is that "restricted oil pressure makes no difference above idle because ECU may involve accelerator pedal".
Above Idle is where works takes place between 1200 to 2500rpm. Not cooling pistons or marginally cooling pistons above idle is amazing not my cup of tea.

The only thing I can think of is this low pressure helps deliver a flat pressure response, easier to manage VVT position.

Does this engine not have oil pressure sensor for the ECU to pop low pressure codes?

The oil pump solenoid should only be ON at idle RPM or not even during idle because then at idle pressure is so minimal it can't cool pistons anyway.
That pump did not get supersized then managed by ECU to reduce high pressure, NOP! It is under-reved on an intermediate shaft already slower (3 chains in total).

I don't want less pressure, I want normal cooling.

++++++++++ Cleaner intake translates as:
Solenoid OFF for nomal oil cooling and cleaner intake valves from less burned oil deposits.
​​​​​​

S-Prihadi

Cali ask : Does this engine not have oil pressure sensor for the ECU to pop low pressure codes?

Of course NOT, no oil pressure sensor on a lot of newer MB engines, except AMG version I think .... MB too stingy... ha ha ha

The piston squiter/sprayers thingy is indeed sad if not fully utilized.
However crankshaft counter weight does splash oil to the under side of the piston. That is how simple 4 to 8 HP Honda portable engine on my portable dive compressor
get its lubrication. They last decent to about 1,000 hours, running at 3,300 RPM from a 3,600 RPM rated engine. Poor soul the little Honda

S-Prihadi

Cali,
Have a go at my log file. This is me back from Surabaya city into Jakarta, where it was peak hour 5PM ish and then crazy traffic jam within Jakarta, till I got home.
So this is a highway driving and then snail pace. Worth 74,440 data points or 248.16 minutes, at 5HZ.

Maybe you can find what you need for R & D as the numerical value is sometimes easier to see in details at this kind of huge data of 5Hz.

I would suggest you first install an oil pressure gauge like I did with the Banks Gauge Data Monster + the extra 4 channels module + the oil pressure sensor to see best result and know
what actual engine oil pressure is your engine delivering at the moment. Approx US$800ish will do + DIY wiring yourself. You then have 3 empty channels at the 4 channels module which you can add other sensors for X, Y, Z purpose.
Here you will from the Gauge ( Data Monster ) get OBD2 logging but most likely the AFR/Lambda value is wrong like mine, hence I do not use it, but you get all other important data.

Here is the last 1 hour before engine kill..... from out of town highway and entering Jakarta city internal highway where the traffic jam is SUCK-BIG time and then I sent my friend home and then
I head home. STOP.





Happy investigation..........

CaliBenzDriver

The fresh crops look really good, thank you for field data. We know how important the cooling is in your tropical latitudes to prevent thermal runaway damage.

Your turbo oil is put through the most extreme torture but your short service interval is the best to compensate. You keeping up good fluids is key factor in preventive maintenance soo-o wise!👍



A key playbook page... 👏
Billy says: "it's CONTROLLED CHAOS and everyone benefits".

Knowing that helps understand some of the things we are dealing with... delayed pistons cooling is not just random chaos, it is "controlled chaos"!

That makes a lot of sense



> Graphs review:


Pressure vs. RPM...
One can see a base RPM and base oil pressures across with spikes related to accelerations.
Both graphs track each other besides a couple interesting spots....


extended pressure colapses
I don't quite understand why pressure gets stuck low regardless of similar engine RPM.


A pressure yo-yo
- In section 1: we have greater pressure than section 2 with similar engine speed 1,250.RPM.
- In section 2: we see idling low pressure while actively driving a hot turbo engine, yes ?

Do you think pealing off a layer of chaos can improve performance and longevity in our engines?



standard pistons oil coolers

​​​​​Tasos pays attention to pistons COOLING JETS at 3:30 as he is rebuilding an engine that needed TLC in hot UAE.

The data comfort me in having limited trust in disabling the pistons cooling while driving. The current ECU logic fosters unfavorable conditions. Instead of being conservative with proper cooling, chaos is blend right in. We don't need oil sample analysis to know why it's burned and how oil carbon coats the valves on low mileage with new intake valve seals.
Master Surya, everything that goes across your sight is interesting.
Let's disable the amazing "oil yo-yo".

including a disabling solution near 16:10.
GM runs oil pressure of 35Psi at idle 👍


solenoid harness connector


M276 oil pump and its control solenoid

(protect exposed connectors from contaminants if possible) - Uses a bypass resistor (greater than 12R) to prevent ECU code.


> Surya's dataset xlsx:
I wanted to draw some of your data but MS-Office365 update is another story. Instead I managed to extract the following average numbers:


Average pressure 24psi.


Average engine 1,240.RPM.


Average vehicle speed 47Km/Hr (30Mi/Hr)

This data average suggests you're driving around with dry pistons due to restricted 24Psi oil.


> Similar YoYo :
There is a parallel between the ECU control of low ALT voltage and the low engine oil pressure.... it's unfinished business that needs attention.

CaliBenzDriver

Master Surya, we may have a case of engine Hail-Mary here.... a sort of engine heart-attack without warning code. It all depends on a li'le screen.


> WHAT:
When the pump control valve gets jammed with pump actuated in low-pressure mode, the engine gets wasted into RIP territory...


> ENGINE RANGE:
We need to understand what engines uses the killer non-screened valves.
ie. check engine range that uses the latest valve that works reliably.

We need to know when screened valves started to be deployed on M276 engines. Let's start with familiar engines (no preference )

It's the same kind of screened valves as inside the tranny valve body. Its been used for decades in every automatic transmissions.

MB has just rediscovered that chunkies floating in burning oil can jam control valve that blows up engine kaput while driving - Need another engine... abruptly crafted failure. Is that another "make a million by saving 2¢" screen

Replacement requires a barrel of cash:
drop engine cradle to drop the oil pan to see pump valve.

Some valves have a defective harness connectors that does not handle hot oil connections - That get a fault code.


> PLAN B:
Unplug the damn valve - Period, done.
Hopefully screened valve don't plug-up... clean oil best.


> Who scores... not your cylinders:
Understanding this root cause you can now Stop Cylinder Inspections for scored sleeves.


This feature stresses the importance of clean engine oil.


++++ GM USA smarter design:
Back in '14 GM already picked up this (Bosch) feature but uses a $5 oil pressure sensor to limp-mode without need to explode engines.
​​​​​​
​​​​​​

S-Prihadi

When I am done with the stuff I am doing on my car, maybe I will do a long run test with 2 stage oil valve wires disconnected.
So far the test with 2 stage oil valve wires disconnected was static in my garage.
The test need high speed run and bad traffic jam combo for good data.
This way we can have a better overall picture of how a traditional mechanical oil pump will behave when there is no intervention from the 2 stage oil valve.

I have X26 connector I can mess easier with for the oil valve, I saw your M276 3.5NA does not use X26 connector and hence it is direct to ECU.
I hope the copper terminal at X26 is SLK 2.8 and the MLK 1.2, because I got the de-pinning tool.
I may want to make a switchable one, by-pass and un-touched using a switch.
Let see what I can do and update you yah.

S-Prihadi

This one is a total stop at the traffic jam. Zero KM/H.
ECU probably set idle mode oil pressure, hence the oil pressure is at approx 16 psi ( hot oil after long drive )




The most common information I read is, 10psi per 1,000 RPM as adequate.
Must find the study to support this common belief

CaliBenzDriver

You say stopped in traffic jam but there's no rpm drop to idle...

I hear that GM uses that pump valve only at complete idle. As soon as engine comes off idle then oil kick into normal pressure. Zero driving without normal pressure.


> Bypass resistor decoy:
- I am thinking about using a resistor around 140.Ohms
then that's a 2Watts: it's non-standard ....I dont have any of those.

- We can stick near .5W with 2x 1/4W in parallel.

- Use an old relay coil laying around could also work if it does not zap the ECU output control MOSFET.
✌️

++++++ Catch of the day:

My valve dirty connector left of balancer

Can that latch survive blind extraction by feel only ??
Yes it did, latch is located on left hand.
✌️

S-Prihadi

When you use brake HOLD, the tranny status is different to simple braking. This is what I mean by true idle at traffic jam, its like gear in N
During brake HOLD that clutch pack ( I forgot the name ) at the torque converter is actually get dis-engaged

CaliBenzDriver

Got to eat your own dog food, right?

Here goes my pump solenoid by-by after 30mn blind search:

my solenoid connector


no oil-in-harness here - Dry connector 👍

Let's see how full oil pressure helps the engine pick ups after red lights ? No need to gun the engine, let's see what the lubed cylinders want to deliver.

My Lambda VIP sensors and cats are going to burn off cleaner from now on.

I've seen the ECU "Temp Gauge" dance around in 105°F weather - Let see what the "Radiator Fan" new behavior is like to manage heat.

Screw solenoid decoy for now, it's Sun day.
Let's ride
🤞

S-Prihadi

awesome........
I can't reach that connector near torsional damper pulley, me have aftercooler blocking... but me have X26 intermediate connector, lucky.
How are you going to define the oil pressure increase under 3,500 RPM when you do not yet have an oil pressure gauge and sensor Cali ?

ADD: The 2-stage oil solenoid on my engine consumes 750ish milliamps. If you use only 140 ohms resistor which will heat up 100 miiliamps, it may trigger DTC I think.
It seems MB has minimum of like under 80% target load not achieved as open circuit. The 5 watts footwell light, the coding setting i seen is minimum as 300 milliamps load if I recall correctly.
I would still go for incandescent 3watt x 2 bulb as load and add 1 amp fuse, because the engine bay ambient temperature is so hot already at 90C for me, one will need wire wound type power resistor capable of 250+ Celcius and not low heat tolerance color stripes one using carbon. Incan bulb failure mode will be open circuit, how about resistor ? Can resistor be overheated and become CLOSED circuit by something melting inside and fusing ?

Here : https://mbworld.org/forums/e-class-w...ml#post8713436

CaliBenzDriver

Master Surya, I am going to trust your excellent research data plots... you have qualified the software amazing behavior in your garage with engine instrumentation.

I believe I have a clear understanding. I am curious to see what cooler oil can do to my M276-NA with its already smooth behaviors.


unleashing caped pressure

> Smooth sailing or not:
I'll be paying particular attention to confused VVT with ramping pressure instead of flat like before.

I expect the rattlesnake pump roller to perhaps be a tiny bit quieter from swimming in cooler more viscous 5W40.

I am game to let oil do it's lube job.