Oil pump solenoids
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W212 E63S Wagon - GSL580 - E63 - E350 - C300
Out Of Control!!
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
No. Just a case of choosing fleet average mileage to meet government mandates over engine longevity. Same thing with the stupid Start/Stop feature. This is NOT unique to Mercedes. Here's what ChatGPT has to say about 2-stage oil pumps:
Two-stage automotive oil pumps are designed to provide variable oil pressure based on the engine's operating conditions. The purpose of a two-stage oil pump is to optimize engine lubrication and improve efficiency in different driving scenarios. These pumps typically have two sets of gears or stages that can operate independently or in conjunction with each other.
The primary advantages of two-stage oil pumps include:
1. **Efficiency:** Two-stage pumps allow for the delivery of the right amount of oil at different engine speeds and loads. At low speeds or light loads, the pump can operate in a low-pressure mode to reduce power consumption. At higher speeds or heavier loads, the pump can engage the second stage to provide higher oil pressure for better lubrication and cooling.
2. **Fuel Economy:** By adapting the oil pressure to the engine's needs, two-stage pumps can contribute to improved fuel efficiency. The pump can reduce its workload when maximum oil pressure is not required, saving energy and reducing parasitic losses.
3. **Engine Protection:** Different driving conditions, such as idling, cruising, or aggressive acceleration, demand varying levels of oil pressure. Two-stage pumps can ensure that the engine receives adequate lubrication under all conditions, helping to protect critical engine components from wear and overheating.
4. **Cold Start Performance:** During cold starts, engines require higher oil pressure to ensure quick and effective lubrication before the oil reaches its optimal operating temperature. Two-stage pumps can help achieve the necessary oil pressure during cold starts.
It's important to note that the specific implementation of two-stage oil pumps can vary among different vehicle manufacturers and models. Some vehicles may use electronic control systems to modulate the oil pump operation based on input from sensors that monitor engine speed, temperature, and load. As technology continues to advance, more sophisticated engine oiling systems are being developed to enhance overall engine performance and efficiency.
That's the text book justification. 50% of the major reasons given are about improving fuel efficiency with the other 50% providing lip service to delivering "adequate" lubrication. What we have found is that in the implementation, lubrication is inadequate for optimal performance and engine health when operating at reduced oil pressure.
Two-stage automotive oil pumps are designed to provide variable oil pressure based on the engine's operating conditions. The purpose of a two-stage oil pump is to optimize engine lubrication and improve efficiency in different driving scenarios. These pumps typically have two sets of gears or stages that can operate independently or in conjunction with each other.
The primary advantages of two-stage oil pumps include:
1. **Efficiency:** Two-stage pumps allow for the delivery of the right amount of oil at different engine speeds and loads. At low speeds or light loads, the pump can operate in a low-pressure mode to reduce power consumption. At higher speeds or heavier loads, the pump can engage the second stage to provide higher oil pressure for better lubrication and cooling.
2. **Fuel Economy:** By adapting the oil pressure to the engine's needs, two-stage pumps can contribute to improved fuel efficiency. The pump can reduce its workload when maximum oil pressure is not required, saving energy and reducing parasitic losses.
3. **Engine Protection:** Different driving conditions, such as idling, cruising, or aggressive acceleration, demand varying levels of oil pressure. Two-stage pumps can ensure that the engine receives adequate lubrication under all conditions, helping to protect critical engine components from wear and overheating.
4. **Cold Start Performance:** During cold starts, engines require higher oil pressure to ensure quick and effective lubrication before the oil reaches its optimal operating temperature. Two-stage pumps can help achieve the necessary oil pressure during cold starts.
It's important to note that the specific implementation of two-stage oil pumps can vary among different vehicle manufacturers and models. Some vehicles may use electronic control systems to modulate the oil pump operation based on input from sensors that monitor engine speed, temperature, and load. As technology continues to advance, more sophisticated engine oiling systems are being developed to enhance overall engine performance and efficiency.
That's the text book justification. 50% of the major reasons given are about improving fuel efficiency with the other 50% providing lip service to delivering "adequate" lubrication. What we have found is that in the implementation, lubrication is inadequate for optimal performance and engine health when operating at reduced oil pressure.
when would LOW PRESSURE oiling be beneficial for these engines? What condition would demand this?
I am not talking about efficiency of any sort. I mean when would the longevity and health of the engine benefit from low pressure oiling?
then:
what are the disadvantages of high pressure oiling all the time?
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
the question for me is:
when would LOW PRESSURE oiling be beneficial for these engines? What condition would demand this?
I am not talking about efficiency of any sort. I mean when would the longevity and health of the engine benefit from low pressure oiling?
then:
what are the disadvantages of high pressure oiling all the time?
when would LOW PRESSURE oiling be beneficial for these engines? What condition would demand this?
I am not talking about efficiency of any sort. I mean when would the longevity and health of the engine benefit from low pressure oiling?
then:
what are the disadvantages of high pressure oiling all the time?
Thread Starter
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04 E55 AMG (totaled), 07 S550 4Matic, 14 E63S
Ha! Found this. I don't think the 2-stage oil pump falls into the category since it is used by multiple manufacturers, but it does speak to your comment. “…the rumor is by the 1990s mercedes was making such reliable and well-made cars that their replacement parts business started to lose the money so instead they loosened the quality control a bit…”
https://youtu.be/hG4rmIsg7eE?si=JtUbz5uSlL_BvuE8&t=112
https://youtu.be/hG4rmIsg7eE?si=JtUbz5uSlL_BvuE8&t=112
The truth is, if you don't like the reliability of a product, you can probably place your blame in precisely two locations: 1) regulations and 2) the consumer themselves, voting with their wallet. If manufacturers thought a car that goes 300k without service would sell better, they'd design and produce it.
Last edited by kevm14; Feb 16, 2024 at 07:23 AM.
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2008 E350, 2012 ML350, 2014 E350, 2015 ML350
I never thought much of the term "planned obsolescence." As I have said elsewhere on this forum, I recognize that it is a real thing that has happened. But people use a very broad brush when using that term (usually to refer to something they don't like) and it almost never is the reason. Maybe I take offense because I am an engineer.
The truth is, if you don't like the reliability of a product, you can probably place your blame in precisely two locations: 1) regulations and 2) the consumer themselves, voting with their wallet.
The truth is, if you don't like the reliability of a product, you can probably place your blame in precisely two locations: 1) regulations and 2) the consumer themselves, voting with their wallet.
. No joke, and I never forget that day.
Thread Starter
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04 E55 AMG (totaled), 07 S550 4Matic, 14 E63S
the question for me is:
when would LOW PRESSURE oiling be beneficial for these engines? What condition would demand this?
I am not talking about efficiency of any sort. I mean when would the longevity and health of the engine benefit from low pressure oiling?
then:
what are the disadvantages of high pressure oiling all the time?
when would LOW PRESSURE oiling be beneficial for these engines? What condition would demand this?
I am not talking about efficiency of any sort. I mean when would the longevity and health of the engine benefit from low pressure oiling?
then:
what are the disadvantages of high pressure oiling all the time?
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Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
OVER 1000 ENTRIES + 50,000.VIEWS
-- Credits to world-class Master Tassos and Master Surya for shinning light upon many excellent uncommon topics and providing inspiration for other like minded spirits. 
-- Full credits to good friends and MBWorld to make all of this possible.
-- Thanks to all the administrators who keep systems humming...
- Should you do it?
Personally given current research conditions I would do it again in a heart beat if I had not done so already but I only call on personal property used for research just like MS.
What is on the line with your decision... is your personal car value going to zero after big-bang theory comes knocking down your dry Cyl#1. (See Eric's casualties in "I do cars" video) - Anyone wants to debate why cyl near oil pump get wasted first? i think it bubly oil when pump size shifts up/down/up air gets jammed creating cavitation.
So far we can say no car were armed terminally during the volunteer experimental test.
Luxury GDI performance was had after 3500.KMi. I used to dislike the clunkiness of the direct injectors work.
Now I enjoy the extended linear performance of multiple shots of injectors + sparks.
- The tranny learned to shift smartly
- The brake pedal became touchy and strong
- The gas pedal became rock-solid responsive
- The superheat eventually receaded completely to standard level.
- The intake plenum lost its old oily car smell
- Gear 1-2-3 now shift normally unlike too short
- The oil is no longer burned black by dry-pistons
- The engine valve trains sound more muffled
- The HPFP sharp lobes really like lubrication
- GDI rich mixtures do kick butts
The Bosch engine control manages individual cylinders to the best of its knowledge with shared Lambda. For us this is an opportunity to have a balanced well timed engine. When cylinder efforts are no longer equal, it throws the timing tics off because rotation is not regularly predictable... that type of individual variation is accommodated by gas timings.
People who are accustomed with 50k sparkplug jobs should add the economy chain tensioners at the same 50k intervals.
He who defeats his solenoid fearlessly... should expect a journey of gradual improvements. Right after unplugging you get great low-end torque like a diesel truck. At the begining at 1100 then all the way down all the way to a balanced smooth idle given my conditions.
High mileage engines may be turned around with specific tune-up care.
Last edited by CaliBenzDriver; Feb 22, 2024 at 02:23 AM. Reason: streamlined
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i drive them all, fast and hard
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Here's your summary:
The BLUF is that our engines use a two-stage oil pump that uses a solenoid to control oil pressure in two stages. With the solenoid connected and operating normally below 3500 RPM, oil pressure is restricted to 2 bar. Above 3500 RPM, the solenoid disables and the oil pressure is allowed to rise to 4 bar. This is done ONLY to save gas and nothing else (thanks to government mandates of higher fleet mileage). As a result, there is sometimes inadequate oil pressure to allow the VVT to fully compensate for wear, etc. There are also problems with pre-mature cam wear, HPFP wear, and the like. Many of us have disconnected the stinking solenoid and have enjoyed better engine health and performance.
Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
BEFORE VVT ...
in the beginning there was darkness... we were after the AMAZING RATTLING GEAR but upon fixing the root cause with rational honesty, the darn HPFP came under controlled timing.
OMG, unbelievable: 1st time in 50kMi!
The camshaft being prevented from jerking by normal oil into tough tensioner without air bubbles, The ECU was able to time the Qty valve of HPFP.
Imagine at 6000 RPM the speed and timing of that signal ... then you'll understand timings requires regularity.
So we dealing with engine oil and the next thing you know the fuel injection is kicking *** and the tranny starts listening to the ECU drum to shift.
> WASTING TRANNIES NEAR YOU:
Strong engines put out Lbs/Ft of torque into the tranny shaft.
How many TCU do you think get to coordinate with ECU timings.... few unfortunately!
We all have different engines, different gear boxes and different useage. What we share are the firmware stack of software methods.
> Significant VIP Team Story:
The first time i witnessed my engine throttle waiting for my transmission to shift going up hill, I literally could not believe it.
The first time this got executed my tranny was not yet shifting machine-gun speed so it was easier to hear the shift steps unfold a 45° California hill.
I was used to all sloppy shifts where RPM are mismatched and use TCC to make up.
When the ECU waits and matches shifts RPM across gear ratio, it helps you understand what's been chewing clutch frictions.
> Fixing that is SIMPLE:
-- Begin with limp tensioners to time the injection pump pressure and perhaps ISM solderless enhancement if still not enabled after 4kMi normal conditions.
The engine output performance is directly impacted by the tranny work: duh!
Slippery clutches... lower the ATF ultra-low viscosity, decrease the pressure for clutch stacks, increase slippage thus high heat.
Less friction = less heat output!!
More friction = burned ATF sludge
OMG, unbelievable: 1st time in 50kMi!
The camshaft being prevented from jerking by normal oil into tough tensioner without air bubbles, The ECU was able to time the Qty valve of HPFP.
Imagine at 6000 RPM the speed and timing of that signal ... then you'll understand timings requires regularity.
So we dealing with engine oil and the next thing you know the fuel injection is kicking *** and the tranny starts listening to the ECU drum to shift.
> WASTING TRANNIES NEAR YOU:
Strong engines put out Lbs/Ft of torque into the tranny shaft.
How many TCU do you think get to coordinate with ECU timings.... few unfortunately!
We all have different engines, different gear boxes and different useage. What we share are the firmware stack of software methods.
> Significant VIP Team Story:
The first time i witnessed my engine throttle waiting for my transmission to shift going up hill, I literally could not believe it.
The first time this got executed my tranny was not yet shifting machine-gun speed so it was easier to hear the shift steps unfold a 45° California hill.
I was used to all sloppy shifts where RPM are mismatched and use TCC to make up.
When the ECU waits and matches shifts RPM across gear ratio, it helps you understand what's been chewing clutch frictions.
> Fixing that is SIMPLE:
-- Begin with limp tensioners to time the injection pump pressure and perhaps ISM solderless enhancement if still not enabled after 4kMi normal conditions.
The engine output performance is directly impacted by the tranny work: duh!
Slippery clutches... lower the ATF ultra-low viscosity, decrease the pressure for clutch stacks, increase slippage thus high heat.
Less friction = less heat output!!
More friction = burned ATF sludge
Last edited by CaliBenzDriver; Feb 22, 2024 at 02:07 AM.
Thread Starter
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04 E55 AMG (totaled), 07 S550 4Matic, 14 E63S
What is on the line with your decision... is your personal car value going to zero after big-bang theory comes knocking down your dry Cyl#1. (See Eric's casualties in "I do cars" video) - Anyone wants to debate why cyl near oil pump get wasted first? i think it bubly oil when pump size shifts up/down/up air gets jammed creating cavitation.
Newbie
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E63 AMG S
I finally got around to doing mine today. I had a spare sacrificial jumper harness in the garage so I cut the wires off to plug both sides. On first start I observed a noticeable decrease in mechanical engine noise. I haven't really had a chance to drive it much but so far so good.
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2014 E550 4Matic
So now, after 2000 miles with oil pump sensor disconnected:
- most definite increase in throttle response from low rpm/closed throttle
- engine seems a bit quieter on startup
BUT…
warm restart rattle is still there. No cold rattle ever, only warm rattle after 10 min - few hours (depending on ambient and oil temp) sitting.
I have the drain back restrictors, but haven’t changed tensioners or cam
adjusters. And my rattle is more of a single lifter tick sound. Makes me wonder about a HPFP issue…?
- most definite increase in throttle response from low rpm/closed throttle
- engine seems a bit quieter on startup
BUT…
warm restart rattle is still there. No cold rattle ever, only warm rattle after 10 min - few hours (depending on ambient and oil temp) sitting.
I have the drain back restrictors, but haven’t changed tensioners or cam
adjusters. And my rattle is more of a single lifter tick sound. Makes me wonder about a HPFP issue…?
MBWorld Fanatic!
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
So now, after 2000 miles with oil pump sensor disconnected:
- most definite increase in throttle response from low rpm/closed throttle
- engine seems a bit quieter on startup
BUT…
warm restart rattle is still there. No cold rattle ever, only warm rattle after 10 min - few hours (depending on ambient and oil temp) sitting.
I have the drain back restrictors, but haven’t changed tensioners or camopening
adjusters. And my rattle is more of a single lifter tick sound. Makes me wonder about a HPFP issue…?
- most definite increase in throttle response from low rpm/closed throttle
- engine seems a bit quieter on startup
BUT…
warm restart rattle is still there. No cold rattle ever, only warm rattle after 10 min - few hours (depending on ambient and oil temp) sitting.
I have the drain back restrictors, but haven’t changed tensioners or camopening
adjusters. And my rattle is more of a single lifter tick sound. Makes me wonder about a HPFP issue…?
It seems once the rattle progresses, it will shake the tone wheel enough until it slips and then either a new camshaft or a tone wheel position readjustment is required "spot weld/super Loctite" to keep it in place --> head covers out, camshaft out, labor -> $$$.
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Academically, replace whatever is damaged. Practically, on the twin turbo M276/M278/M157 getting there is so painful that once the timing covers are open to replace the chain tensioner, may as well replace the VVT ($$$), button it up, and be done. Having to come back for the "skipped part" is a matter of personal choice and budget.
Thread Starter
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04 E55 AMG (totaled), 07 S550 4Matic, 14 E63S
So you are saying the bad tensioner is the source of that slamming that eventually shifts the reluctor? Is there another issue that results in cam lobe failure?
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Keeping in mind that failures on the twin-turbo for the M276/M278/M157 are related since they are cousins, here are some links to review.
https://mbworld.org/forums/mercedes-...ml#post8924853
From Master Prihadi, the solenoid man
https://mbworld.org/forums/e-class-w...ml#post8848549
and the video showing what the reluctor wheel looks like and what synching it is.
Last edited by JCM_MB; Feb 23, 2024 at 12:27 PM.
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
This Modern Engine Issue Can Wreck Your Next Build... Timing Chain Nightmare On Our ML350 Project (youtube.com)
Speaking of M276s. This is an early, N/A one. But does this cam lobe issue they describe afflict the V8s in any way?
Speaking of M276s. This is an early, N/A one. But does this cam lobe issue they describe afflict the V8s in any way?
One thing from the video, he may have a point that the VVT wearing out (or low oil pressure) could initiate damage on the cam lobe. However, extending from my previous comment (and now answering your question) I would speculate the cam lobe issue is downstream of the tone wheel failure, unless it is due to poor manufacturing which is statistically possible.
To the point of this thread overall, the two most important things I get so far:
1 - Keep these engines lubricated the best way possible: one is normal oil pressure at all engine speeds. From there, normal wear should happen and periodic maintenance will keep us from an engine failure.
2 - Parts wear, but we do not want to accelerate the wear if possible; therefore, when there is a sign of problem -> ADDRESS IT quickly before it snowballs into $$$$, or engine failure.
My 2c.
Last edited by JCM_MB; Feb 23, 2024 at 03:00 PM.
Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
OIL PRESSURE VS. CAM ISSUES
The standard repair of this engine class is the wild VVT startup rattle when the single lock pin is worned out.
The cam lobes drive the cam forward during normal rotation. This camshaft motion drives the VVT forward, squeezing oil out of chamber and catching the lock. Then the whole VVT drives the chain forward using slack from limp tensioner squeezed flat.
This degree of cam freedom impacts ECU performance due to timing randomness.
The soft camshafts getting grooved is from the dry friction of follower arms. Steel in steel makes bad grooves but you imagine the steel shaft in dry aluminum bearings - This is the authentic "forbidden glitter". the kind that jams pump solenoid and spins crank bearings.
That's why we don't mess with steel shafts spinning over aluminum frictions points: that can get expensive quick.
Wider engine gaps call for higher oil film viscosity than ultra thin blends. Our 8Qt sump has plenty of reserve. Let's pump our oil until MB limits its engine to 4Qt sumps to save weight like on Toyota.
The cam lobes drive the cam forward during normal rotation. This camshaft motion drives the VVT forward, squeezing oil out of chamber and catching the lock. Then the whole VVT drives the chain forward using slack from limp tensioner squeezed flat.
This degree of cam freedom impacts ECU performance due to timing randomness.
The soft camshafts getting grooved is from the dry friction of follower arms. Steel in steel makes bad grooves but you imagine the steel shaft in dry aluminum bearings - This is the authentic "forbidden glitter". the kind that jams pump solenoid and spins crank bearings.
That's why we don't mess with steel shafts spinning over aluminum frictions points: that can get expensive quick.
Wider engine gaps call for higher oil film viscosity than ultra thin blends. Our 8Qt sump has plenty of reserve. Let's pump our oil until MB limits its engine to 4Qt sumps to save weight like on Toyota.
Last edited by CaliBenzDriver; Feb 23, 2024 at 10:55 PM.
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14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
I'm still not a full believer that a silent code associated with something like this doesn't do something where the ecu reduces power to some extent. No one in the other thread neither dug enough into the coding or did a before and after dyno comparison to be certain. My point being, it sounds great on paper but I'd like proof before I simply start unplugging the solenoids or videamo coding without fully understanding the "yes/no" parameters associated with that line of coding. I'll let smarter brains than I start playing with it.
Also agree that this is a likely contributor to the cylinder wall scuffing. It's either a lubrication issue, or an overfueling issue causing cylinder washout.
Also agree that this is a likely contributor to the cylinder wall scuffing. It's either a lubrication issue, or an overfueling issue causing cylinder washout.
Been hesitating to report this, but I do have a negative behavior associated with the sensor unplugged vs being plugged in. In colder weather (40(s)f and below), when I first drive the car if I don't drive it hard enough for about 5 minutes it'll stall /bog out under high load/low throttle. I've stalled it multiple times on a hill in my neighborhood on the way to work in the morning .
Did the transmission adaption reset, and no change. Replaced my throttle pedal, no change. Out of morbid curiosity, plugged in the sensor and it went away. Unplugged it overnight, it came back.
I'm torn as I feel the pros of having the sensor unplugged outweigh the cons. However, this behavior goes back to what I initially said near the beginning of the thread that I'm hard pressed to believe the sensor doesn't have some other affect associated with it other than just oiling. Clearly it does. Or I shouldn't be able to do this.
What this tells me is the ecu is telling the sensor to reduce/increase oil flow to some extent based on load and temps. While the primary purpose may be emissions and fuel efficiency, that clearly has an effect on low rpm drivability that may need some adjustment in the ecu to compensate for this change.
