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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by kenneyd
I read through the post, I did not see any explanation of why Mercedes engineered this way. Not that I was expecting us to know exactly why, but does anyone even have any good ideas of why Mercedes engineered it this way?
To get better gas mileage numbers. That's all. It's just like the stupid start/stop that all new cars have. It's all about the numbers and stupid laws. And it's not just Mercedes.
So, I know people have tested it on the V6 NA and TT, has anyone fully tested it for the M278/157? After reading all this info I'm tempted to just unplug the connector for good on my M278.
So where is the location of the sensor we are unplugging? Other than increased low end torque has anything else changed for the bad other than a shadow code?
Originally Posted by JettaRed
Nope. No CEL or limp mode. Actually, the car feels stronger on the low end. The solenoid is normally open (full flow) and is restricted only below 3500 rpm. You will get a DTC P06DA00 (open circuit), but not a CEL/MIL. Mercedes has even issued a TIP referring to the solenoid as "non-essential". Not sure where the wiring harness connects on your engine, but on the M276 it is right in front next to the crank pulley on the right side of the engine.
So where is the location of the sensor we are unplugging? Other than increased low end torque has anything else changed for the bad other than a shadow code?
Mojo, you have a very impressive upgrade package.
You should get an oil pressure sensor if you don't already sport one.
Oiling is an old topic but it is still super important not to temper with.
The only thing bad is throttle is very responsive after 1kMi relearn period.
Bosch engine control took away some oil... now we can have it back.
Last edited by CaliBenzDriver; 11-18-2023 at 06:00 AM.
Take a look at the WIS PDFs I attached. I am not sure myself (generally same area as M276) but the car is going on my Quick Jacks this morning for unplugging.
One downside is if someone were to plug it back in after being unplugged for a long time - what happens? Would it be seized closed? Or might it seize open? I mean it's protected and oiled so even if left unplugged it shouldn't seize....in theory. Nor should it seize during operation (yet it can).
Take a look at the WIS PDFs I attached. I am not sure myself (generally same area as M276) but the car is going on my Quick Jacks this morning for unplugging.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
OK, here's a newer version of Kevin's document.
Again, however, on the M276 engine, the wiring harness attaches to the internal wire to the solenoid through the block on the front of the engine to the right side of the crank pulley.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by kevm14
Take a look at the WIS PDFs I attached. I am not sure myself (generally same area as M276) but the car is going on my Quick Jacks this morning for unplugging.
One downside is if someone were to plug it back in after being unplugged for a long time - what happens? Would it be seized closed? Or might it seize open? I mean it's protected and oiled so even if left unplugged it shouldn't seize....in theory. Nor should it seize during operation (yet it can).
I keep going back to the Xentry TIP that says the solenoid (valve) is a "nonessential" part. And, FWIW, you can access the wiring harness from above the engine (on the M276) though it is probably easier to reach from below. I had to remove the intake duct work on the right to more easily reach it.
I did post elsewhere that you may not notice significant responsiveness because the turbos tend to mask it. But on a non-turbo M276 3.5L the change is quite noticeable.
It's raining and the Quick Jack is in the other bay. So I did a quick visual from the top with a light and mirror. This seems like the most obvious thing but is this the valve in question? That's the crank pulley in the mirror on the right of the image. And in terms of engine orientation this is to the right of the crank pulley (always when sitting in the car, btw). Access from the bottom looks tricky so I might attempt from the top. Problem is I need to ziptie the plug out of the way so it doesn't rub against the crank pulley.
It is a 2 pin connector (getting warmer I think), and the two wire colors are red/green and green/violet. Of course the harness is nicely taped up but I may give it a second look.
Looks like it shares the ground with the right upstream O2 sensor. There is also some "connector sleeve" for this shared ground but even if this were accessible and I unplugged it, it looks like it would kill the ground for that O2 sensor. No bueno. I see no other place in the harness (other than at the ME) to disconnect this.
Or, could do a little snippy snip at pin 81 at the ME (ECU and not sure which plug). Would be easy enough to reconnect though obviously cutting wiring harnesses is....hacky.
Just for completeness here is the Z7/36z2 ground sleeve connector location (maybe). Not recommending doing anything with this though.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by kevm14
It's raining and the Quick Jack is in the other bay. So I did a quick visual from the top with a light and mirror. This seems like the most obvious thing but is this the valve in question? That's the crank pulley in the mirror on the right of the image. And in terms of engine orientation this is to the right of the crank pulley (always when sitting in the car, btw). Access from the bottom looks tricky so I might attempt from the top. Problem is I need to ziptie the plug out of the way so it doesn't rub against the crank pulley.
It looks like it. It has one of those connectors that looks like a periscope and has the clip you need to pull out and squeeze, much like the cam position sensors on the top of the engine. One way to know for sure is to disconnect it and then scan for codes without even starting the engine. If you get a currentP06DA00 for the engine module, then that was it. If not, plug it back in and keep looking.
I zip-tied my lose connector to the coolant hose to keep it out of the way of the crank pulley. I also wrapped it with some self-fusing waterproof tape and then aluminum duct tape (for added structure/strength).
Missing oil sensor:
There is a oil tap/plug on the oil filter base to use for a manual oil gauge or a sensor.
That is where MAX pressure is found near pump. MIN pressure is found all the way to rear bank1 where HPFP only gets what pressure is left over.
Meaning the pressure at filter is only a partial overall view. There is a pressure leakage right at timing cover that has no gasket and no silicone... we have not figured why MB wants no oil seal at timing cover.
> Proof in the pudding: From the oil filter location you can chart pressure vs. RPM to evidence how ECU is forcing low-pressure below 3500.RPM.
The engine PDF description almost read nicely... Daimler wants "warm up the oil"....but there is NO FEEDBACK CONTROL to limp-mode when cheap valve gets stuck on low-pressure. It blows-up the engine piston/crankshaft bearings RIP.
managed pump pressure...
Now we know why the piston rings get stuck with burned oil carbon... Then it causes high blow-by crankcase pressure that blows oil out of everywhete possible: seals, plenum, vacuum pump, "oil-in-harness" CPS, ...
The design idea to warm up is all right and if it was well developed - When quarts of oil get vaporized you'd think it is hot enough so they can quit driving on low pressure to warm up the engine.
This feature is like the "Job of a summer intern" that never got completed - IT'S UNSAFE!
There is s big unspoken design gap about the VVT gears. They rely on pressure to work well. Low pressure virtually disablestge non-ratcheting tensioners and VVT that has to lock in neutral. That's the genesis of engine rattle wear.
> Idle quality:
Listen to the idle quality improvements with legacy oil pressure !!
The camshafts sound is quieter
The HPFP is much quieter
The tensioners hold the chain tight and
The RPM is evenly smooth instead of up/down
The cold engine warm-up high-idle is much shorter
> Closely matched Trims:
Trims are always somehat matched to engine else a CEL flag is raised. More fuel means more power, that what we get here! Better burn allows more fuel delivery at lower RPM.
Here is how...
The smoother camshaft timing driven by the tight tensioners and the pressurized VVT gear allows the HPFP Qty valve timing to be exact in regard of 3/4 lobes showing up with minimal variations.
This means fuel pressure is well regulated not just averaged. In turn that allows for injector trim to chart better fuel maps from cleaner lambda sensors.
It does take about 1000Miles to reach that stage of improved engine driveability. Meaning improvements happen gradually starting from the first 10Miles test drive.
> Unnecessary chaos:
This feature introduces so much drama that its impossible Daimler isn't aware of it's negative impact with zero benefit besides service needs.
Last edited by CaliBenzDriver; 11-18-2023 at 02:09 PM.
Just got back from the test drive. I unplugged the valve, went for a short drive, and then pulled 3 psi from each tire and went for a longer drive. First, the ride is way better so I think I'll keep it that way and second, I couldn't stop driving the car in general. Let me explain.
I cannot believe how snappy it is on a free rev right from idle. This translates to the rest of the improvements which I will summarize.
1) The part throttle response/torque delivery from a low RPM is totally smoothed out and stronger. I'm talking like 1000-2000 rpm situations where you roll into the throttle. It was unsmooth and would kind of surge before. I even threw a wastegate vacuum harness at it as well as a vacuum pump check valve, thinking that might help. Nope, it was the damn VVT not reacting right to low oil pressure due to the oil pump valve bleeding pressure at low RPM.
2) Idle quality is improved in general. It's just smoother.
3) Revving response in park/neutral as the video shows is extremely crisp. I can't believe it actually.
4) And here's one that really blows me away. I thought I had MCT clutch chatter, like when slowly moving off the line, up a slight hill or something. I just figured, hey, it has 102k on it, it's going to chatter a little bit. Well, the MCT engagement is COMPLETELY smooth now. Like I said, I am blown away. Forward, reverse - it's totally smooth. I was convinced it was the MCT! It was just the engine running unsmoothly.
5) Actually the transmission shifting itself seems smoother to me (up and down).
Now do I think this really adds any peak power? No, because the oil pump valve would already be closed in those situations. But for all the situations where you are at part throttle, especially at lower rpm, this made a huge difference. Oh, and no CEL. Engine sounds healthy and strong. I have zero concerns about any downsides to this. I think it is all upside, incredibly.
Alright, now someone else try it! You're welcome in advance for bringing this to the W212 AMG forum, even though it seemed to be known to the M276 community already. Cali, are you the one who made the comment on a Youtube video that said to unplug this valve? That comment is what started this whole evolution for me.
Between this and the tire pressure change, like I said above, I couldn't stop driving it when I was done.
Just got back from the test drive. I unplugged the valve, went for a short drive, and then pulled 3 psi from each tire and went for a longer drive. First, the ride is way better so I think I'll keep it that way and second, I couldn't stop driving the car in general. Let me explain.
I cannot believe how snappy it is on a free rev right from idle. This translates to the rest of the improvements which I will summarize.
1) The part throttle response/torque delivery from a low RPM is totally smoothed out and stronger. I'm talking like 1000-2000 rpm situations where you roll into the throttle. It was unsmooth and would kind of surge before. I even threw a wastegate vacuum harness at it as well as a vacuum pump check valve, thinking that might help. Nope, it was the damn VVT not reacting right to low oil pressure due to the oil pump valve bleeding pressure at low RPM.
2) Idle quality is improved in general. It's just smoother.
3) Revving response in park/neutral as the video shows is extremely crisp. I can't believe it actually.
4) And here's one that really blows me away. I thought I had MCT clutch chatter, like when slowly moving off the line, up a slight hill or something. I just figured, hey, it has 102k on it, it's going to chatter a little bit. Well, the MCT engagement is COMPLETELY smooth now. Like I said, I am blown away. Forward, reverse - it's totally smooth. I was convinced it was the MCT! It was just the engine running unsmoothly.
5) Actually the transmission shifting itself seems smoother to me (up and down).
Now do I think this really adds any peak power? No, because the oil pump valve would already be closed in those situations. But for all the situations where you are at part throttle, especially at lower rpm, this made a huge difference. Oh, and no CEL. Engine sounds healthy and strong. I have zero concerns about any downsides to this. I think it is all upside, incredibly.
Alright, now someone else try it! You're welcome in advance for bringing this to the W212 AMG forum, even though it seemed to be known to the M276 community already.
Cali, are you the one who made the comment on a Youtube video that said to unplug this valve? That comment is what started this whole evolution for me.
Between this and the tire pressure change, like I said above, I couldn't stop driving it when I was done.
Awesome roaring!!!
> Transformation:
I am glad we could empower you with this 5mn free fix.
You're going to notice more gradual improvements in the ballpark of what you've described... the whole thing is an unbelievable transformation, isn't it?
Now my engine literally ticks like a Swiss watch.
Enjoy!!
> Furthermore... with these creds :
There are other fancy bits of chaos we can help you cancel.
-1- ALT YOYO :
The next thing you may be interested in is making sure your Alternator voltage doesn't drop below 12.6V during acceleration and certain conditions -
This condition is unrelated to solenoid chaos.
How: learn to display "Batt sensor vitals" on you instrument cluster and keep an eye on what it does - Go ahead start a new thread when you're up
-2- Wandering rack:
Again it's one of those mediocre performance you don't know your car has until it is fixed.
-3- Open Choice:
For 3rd you can elect to fix the popular "Banging Tranny shifts" or "Battery drain"...
Help yourself to fixes in my signature links. Not all of it is entry level but free it is.
> Metadata....:
Once you realize the best bugs are concealed without easy ways to be discovered, then you go on a hunt to check and question things out.
Marginal "GND posts" is nice outcome and pretty simple to fix.
✌️
Last edited by CaliBenzDriver; 11-18-2023 at 05:45 PM.
Reason: Fix ALL...
14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Originally Posted by kevm14
Alright, now someone else try it! You're welcome in advance for bringing this to the W212 AMG forum, even though it seemed to be known to the M276 community already. Cali, are you the one who made the comment on a Youtube video that said to unplug this valve? That comment is what started this whole evolution for me.
Between this and the tire pressure change, like I said above, I couldn't stop driving it when I was done.
OK. I'll take a shot at it. Throwing it up to replace 2 splash guards anyways, so why not.
Interesting. Any changes noticed in oil warm up time?
The topic of engine temperature is an interesting one. It is regulated by the opening of a smart thermostast remote controlled by the ECU.
Oil on the end is cooled by heat exchanger that trades heat inside with circulating coolant.
One issue this engine does not have is warming up its oil. It is a non sense to stop piston sprayers to super heat pistons and then spray them later to earm up the oil - Non sense doing that! Heat stress cracks pistons and create blow-by with carbonized rings.
If rooky developer "stops spraying to warm up the oil...", then you wonder if fractured parts are hot enough ???
The hot parts are located near where combustion takes place: pistons and heads.
Oil warm up faster by circulating it around to grab heat from hot parts than superheating parts dry.
If these have an oil thermostat it doesn't work like a lower performance engine. These are known to take upwards of 12-18 minutes to fully warm up oil. They are also known to over-cool their oil on a highway drive during a cold day. That's why he's asking.
11-17-2023, 10:32 PM
