WRC-LVR

my opinion is yes to this : So the question is, is it receiving a signal from something and lowering boost in response...YES it seems to be Keep in mind this happened suddenly one day, with only 29k miles on it, not over time. You have a mechanical or sensor issue that happened all of a sudden.

I just saw your reply stating there are 4 knock sensors. Can you let us know where on the engine they are located? BTW I am a little confused as the logs you sent me for analysis have 8 knock sensors logged.... with differing values...!!!

the timing in the logs you sent me has advance and retard per cylinder. . IMHO the retard per cylinder is used to "finetune" the spark delivery and is probably adjusted using the nearest knock sensor, in real time. Base Timing is read from the crank position sensor and camshaft position sensors and fed into the ECU for starting the calculations, taking into account desired load and many other parameters including throttle opening, rpm, temp, rate of opening or closing, other factors


The logs you sent me do show boost building quickly, then dropping off. The O2 sensors are logging varying voltages ( how old are they ,might need changing if 40K miles ??) , your STFT varies usually 0 to -3% BUT your LTFT typically shows up to 12% during acceleration . Are you sure the correct PID is being logged for that? LTFT being off that far may be indicative of a fueling issue ( going lean). STFT usually is +/- 1%, if dialed in correctly. Has the fuel/ injector system / fuel pump/fuel filters been serviced or the injectors cleaned?

Based on the sudden appearance of the issue, I would try to match the symptoms using what if analysis to narrow down possible culprits. It is why I asked for the control system manual to try to understand how the control systems work. If we can get an answer to if the O2 sensors are wide band type not narrow band type and the ECU uses them to control boost, fueling and timing, that would be great.

Chevota

the 4 knock sensors are scattered on top of the eng between the cyls. i assume it guesses which cyl is noisy.
wide band o2. nothing has ever been cleaned other than sea foam in the tank now and then. o2 seems to be working.
if i recall, timing is supposed to be 20 while under boost, which it is sometimes. under what psi i forget.
i plan on adjusting misc setpoints, one at a time, and see what happens. that hp tuners program can change some things but not all. i guess only what items they have time to figure out, and probably only what they think is needed.
oh, and no instructions either, and very few people use it on a benz so theres next to nothing to compare to, so basically ill be wingin it.
also, that control sys info pdf is only part of the picture, many more things are at play. i know some of them but not all.

WRC-LVR

Good to know. Each one will be specific for a pair of cylinders across the V. Minor knock can be reduced by thr spark retard function. but it is just a small modifer to the total spark to that cylinder. Big knock will have the ECU shutting down boost, retarding timing etc immediately.

BTW too rich a mix can cause knock as well as too lean a mix. Just be aware of that. Slightly plugged or old Q2 sensors can be slower to respond under high loads so think about that in relation to your FT's

Timing will vary from about 35-45 degrees BTDC under constant light throttle to 0-5 BTDC at full load. Best to log a WOT starting at 1000 rom to 6000 holding it in 2nd gear.

Yep. I saw that issue with the OpenECU tuning programs in the Mitsu EVo world. And no real DIY just lots of posts do this maybe , maybe not. IIRc the Mitsu ECus are bout 70% figured out now.

I know how you feel, But you do have the OE tune you had on there so you can compare tables and routines to the benz OEM tune and tables. Just be very careful not to demand more boost or change timing advance until you have spent real time in it.

i would be interested to know if the Q2 sensors are narrow band or are wide band type. If wideband type the ECU may configure the timing, boost based off the o2 sensors in real time with default tables in emergency situations. Makes real sense as it will produce more power and use less fuel. Other cars are doing that now.

Chevota

The previous msg was from my phone, at work, so it was sloppy and rushed.
The knock sensors were staggered, not a neat line down the middle. I assume it looks at all the sensors but applies that to what cyl just fired. I'd also assume it looks at overall noise and tries to ignore the steady stuff, but I may be giving it too much credit.
Yes, wide band O2. Apparently there is no open loop function. I always thought that would be cool to have that, but now that I do, I no longer think it's cool. They seem to respond quickly, but I don't really know what quick is. I've been using the painfully slow data via Bluetooth up until a week or so ago, so it's all super fast to me now through HP Tuner via usb.

Any idea how/where the ECU gets the Torque data it spits out? Because it's WAY off. According to that I've had it up to 600hp and 700Tq, so of course it's pulling boost because it thinks it's maxing out.
So it's logical to assume that the Tq calc, or more likely something that feeds into the Tq calc, is wrong.

So here's what I discovered the past few days: Increasing Torque Limits did nothing. Increasing Fuel, nothing. Then I put all back and only lowered Exhaust Temps, by 6% (seemed like a reasonable # to try) and I got ~35% of my power back. So it appears Ex Temp is what was doing it, but how? Why? It's not like the temp chart was wrong, so wth? Again this leads me to believe it's a glitch...

Assuming I can't find the issue, I could simply lower Ex Temp #'s until I have all my power back, but will that do something else I won't like?
Apparently the Torque PID uses that temp chart too because it dropped by 100. So if I continue dropping temps to net power, then the Torque PID will likely end up very low and I worry the Tranny uses that value for line pressure. I'd imagine it's simply high/low line psi. Anyone know what the threshold is?
Also, how do people est power once the torque PID is ruined like that? Does everyone switch to accelerators, or just use it as a reference value?

WRC-LVR

I’ll try to give my takes- never assume anything. If I was you, i would change the front O2 sensors as they do have miles on them

1.To properly estimate power and torque you need 0-60 time, exact weight of the car as driven at that time including driver etc. Use the online calculators.

2. Full time closed loop is def the way to go, but it requires very fast accurate response from Q2 sensors. Open loop goes by the tables with input from sensors, rpm, load calculations etc etc Narrow band sensors are only good for 14-15 AFR. Wideband sensors range from 9-18. Required if full time closed loop control other wise you need tables etc..WOt then goes to open loop and tables etc

3. Re the where does the MB get the torque calc from? The real question is what data does HP tuners use? Ditto for Torque Pro. Strongly suspect they are not correct and are reading just a part of the calculation or applying an equation to data being read. MB will use all the available data from the engine, transmission( gear ), speed , load etc

4. Fast Data trumps all…Good work

5. Knock is looked at by the ECu thru the knock sensors, it looks for certain frequency and voltage at that frequency, so it filters the data and then applies that to the timing routines probably on a per cylinder basis as well as overall.

6. The camshafts have variable timing – think about that .. don’t know if you can log camshaft position in terms of advance retard but that might give insight

7. OK so does the car actually have EGT temp sensors? I dont see mention of them in the MB engine manual overview. So I don’t think so, unless you have installed them. so it is being estimated somehow ? the O2 sensors are being read in a way to estimate EGT ?

8. IIRC that EGT has a temp hump …too lean = cooler , Too rich cooler .. I don’t know what you mean by "tried lowering exhaust temp" …it is gonna be dependent on air and fueling and timing ( to a degree) so my thought is “moving the EGT” is actually doing something to the AFR and possibly moving the timing. LOG knock !!! Correlate that to AFR O2 sensor readings. And think about using a wideband in the tailpipe. most engines make peak power at 12.0 - 13 AFR. Too rich and engine loses power, too lean you risk knock and holes in expensive things





So EGT goes up if the spark is later in the combustions cycle as the combustion takes place later in the cylinder. Too late timing will stress the turbos hot side leading to failure. However peak cylinder pressure goes down as the hot gases occur later and start escaping faster, therefore torque goes down too. It is one way of managing the stress placed on transmissions, driveline and axles. OTH early timing will increase the peak cylinder pressure the engine sees increasing torque and the engine temp will be sl higher as less heat escapes thru the exhaust. EGT goes down due to that as well. Too much timing leads to knock and control by the ECu to manage that.



If you have that WOT run on one gear ( second ) from 1000 to 6000, you can better stimate power from that. Get used to doing pulls to look at data generated. Most software can output that to .csv files so you can check in Excel



Last but not least, you can take your car to a dyno and it will give a good estimate for the real power at the wheels while you log whatever you want during the runs.

WRC-LVR

When using a wideband, you have to make sure it is 1) in right location 2) properly calibrated and 3) the software you are using has the proper equations to convert the signal. The gauge reading might be ok but the signal out put to your software needs to be properly setup to display the range and correct reading.

when using a EGT as aid to tuning on turbo car: 1) is it calibrated? 2) installed before the turbo, 3) proper depth into manifold 4) if logged then proper equation to align signal with correct temp

WRC-LVR

https://www.enginebasics.com/EFI%20Tuning/EGT%20vs%20AF%20Tuning.html See quotes " Many people think that the leaner you go, the higher the EGT gets. This is also incorrect. Peak EGT occurs at stoichiometry- about 15 to 1 for our purposes. If you go richer than 15 to 1, EGT will drop and if you go leaner than 15 to 1 EGT will ALSO drop. It is VERY important to know which side of peak EGT you are on before making adjustments. It is safe to say that peak power will occur at an EGT somewhat colder than peak EGT. You can sometimes feel a lean of peak condition as the mixture is hard to ignite and power will be down a bit as well. Once the AFR gets close to 17 to 1 at WOT, generally the engine will start to lean misfire." Boom as pistons block will get holes in them rods will bend etc

"Most tuners always recommend to begin jetting or programming from a known very rich initial setting and carefully leaning until torque falls off slightly, then going back richer to the point of max torque. Note the EGT at this setting. Be aware that altitude, barometric pressure and ambient air temperature may affect this optimal temperature to some degree"

"It is really the AFR that is important, not the EGT. Most engines will make maximum power at an AFR of between 12.0 and 13.5 to 1 however, the EGT may vary from 1250F to 1800F and is dependent on many factors. "

If you are tuning from the EGT temp and it drops, then the AFR was/is probably close to 14-15 . You wont know what side of 14-15 you are on though, rich or lean. Get a wideband, install it and log it.

Chevota

Well, when I say lean I mean Stoich, which I assumed was assumed? At least back in my hotrodding days it was. People ran ~12:1 to Stoich, and that was your window for everything. Keep in mind my day was carburated because EFI sucked, and imo still sucks. Sure the potential for it to work is there, yet it doesn't.

The EGT is just a table of values to tell the ECU what it predicts the Ex temp is. So you lower the #'s to see if it's holding you back. The funny thing is the Ex temp calc is disabled, from the factory, yet changing it works. There's a LOT of stuff going on in the ecu and the HP Tune only sees some of it. To keep in mind when things don't work how you might think.
The only actual egt measure is for the cats, but who knows, it could be virtual too. Don't really care, it's not my issue.

The Torque reading is from a PID from the ECU. All I can say is the app Torque Pro gives a much different torque value, about half, so I don't know what to think. Unless there's more than one PID, but all the programs I use can only see one for torque so I assume just the one.
So basically my only real torque measurement is seat of pants and how it spins the tires, if it can. Trust me, when power is back I'll know it, but so far I'm nowhere near it.
I see people saying they did this or that mod with HP Tuner and they gained xx power, but I know they're use that torque pid to get it. Dyno time is something very very few people do, and usually only do once. So my question is; does that pid not work right period, or only not work right for me?

Regardless, that PID's # is really about chasing clues to my actual problem. Is my problem/glitch feeding into that PID calc and causing the power drop? Is so, what is it?
Meanwhile I've altered a bunch of settings and now just need to go test it. Basically I programmed it to make ~1100 HP so I won't be surprised if I get my power back, but it won't tell me what the issue is either, it's just to see what happens and maybe squeeze a clue out of the results. It also won't prevent the tranny from stepping in and killing it, but I have no control over that.
It may, however, tell me what PID the tranny is using to pull throttle.

Can't get good data in 2nd gear, the tranny is too busy pulling throttle. So what I've posted is as good as it gets, so far. I have made a 0-60 run and one nice 0-80, only to be screwed by the HP tune program not recording all my data. The opportunity for such runs is rare and it's very risky so I'm pissed it was for nothing.
The trans pulls throttle in gears 1-3, so 4th is the only gear of use for a 1 to 6k run, which would be 20-130mph and an impossibility where I live. Even flooring it for more than 2 seconds is not easy, and risky.

I can't start in 2nd anyway, it just downshifts to first. Yes, even in manual but I suppose altering the throttle command could fix that. So between the car not cooperating, and the data speed, I'm still screwed. The data is faster, but still not fast enough. Eg Friday I bounced off the 6200 rev limiter, hard, but the tach in HP Tune never hit 6. Or it might say I'm making 600hp, when the throttle is at 20%. So I still have to guesstimate where each data line is actually supposed to be. I also don't know if the data is consistently off or randomly off. I see the Ign timing is lagging throttle, but then other times it's reversed. Does it flip flop only once in a while, or maybe all the time? The data also freezes so I can't tell if it's froze or holding steady.
Frustrating huh? Like a needle in a haystack, in the dark, with the wind blowing.

So don't think of all this as tuning an engine, it's only to find my problem. The engine, minus the problem, ran great and no need to change it. HP Tune is just a $700 attempt at finding the problem.

Chevota

Well, I made a tune via HP Tuners and it worked! I don't think power is quite 100% but pretty frikkin close. Not bad considering I don't know what I'm doing, and don't know what half the things in there are.
My problem is still there, I simply set it to make more power than it's capable of so my net power with my loss ends up where I want it.
It also runs cooler, quieter, better throttle response, and less knock sensor noise and timing retard.

As a bonus, and I can't explain why, the torque converter locks up much earlier and stays locked much longer so it engine brakes like a stick! This is something I wanted but never thought I could have. So now when I'm coming to a stop or in traffic, I just let off the gas it slows down nicely. I hardly used the brakes at all in traffic today. Red lights I only needed to brake the last few feet. And that's not manually downshifting either, it downshifts nicely on it's own, which I don't know if I did that or simply never noticed because the converter was loose. Whatever happened, it's awesome.

So far no clue to my problem but at least I have power again.

WRC-LVR

just be very careful in tuning. Again you don't know what the AFR is unless you log it with a wideband. Also messing with the tune as you have indicated has done something to the tranny code. be careful!!!! Unless you can afford a new one :-)

Chevota

The tranny is it's own entity, so all I can do provide false data to it, I cannot alter it. I'd pay to be able to alter it, but so far nothing like that exists for Joe Blo.
The AFR doesn't worry me at all. I do log it, and I can also watch it live as I drive if I wanted, but boost is all I watch. AFR has been working just as I set it and is probably one of the easiest things to adjust on it. Something not so easy is boost. Or that cool torque converter thing I did, because it came at a price. It screwed up my cold idle which I had just how I wanted it. So how to make it work and keep my idle is something I'll just have to figure out by trial and error.

Same with the boost actually, so I fine tune it and squeeze more from it. It seems to pull good at lower speeds and lays rubber, but after flooring it at higher speeds where I get traction I can tell it's still lacking.
There is just short of zero information on how to use the program, which I assume is because they offer instructional classes that cost $. Money is the root of all problems isn't it. People create problems for you, in an effort to get you to pay $ to make it go away. I refuse to pay for a class so I'll just have to figure it out on my own. Plus, 98% of classes I've taken in my life were next to useless, and I expect nothing to change here. I'd bet the class doesn't cover even Mercedes anyway. They're different than GM and the popular cars, and since the popular stuff is where the $ is, that's were people focus and MB is left in the dark.

Thanks for the word of caution tho I think my #1 risk is rupturing my intercooler, so I've been eyballin availability and may buy a spare.

Since this tuning software wasn't any help in finding my issue, I think my next step is finding the oem factory load for my ECU. I think loading a fresh copy on will fix my whole problem, but only one way to find out.

WRC-LVR

" The AFR doesn't worry me at all. I do log it, and I can also watch it live as I drive if I wanted, but boost is all I watch. " It is not clear how you are logging AFR. If you are not logging via wideband before cats, how are you logging it? If you are logging based on the cells on a particular AFR table that the load calculation calls for, I would be extremely cautious. Just because the AFR is being called for doesn't mean that is what is happening in the cylinders. That is why you log independently, That is tuning 101. It is a fact that many things can affect the AFR. Temp, baro, injectors not delivering correctly, fuel pump not delivering correctly. fuel pressure regulator not working correctly. The ECU may think it is ok but the called for 13.0 AFR may actually be 14.5. Not great if it is WOT. If the MB system is still u ing narrow band O2 then the Ecu can't know the actual AFR.
Please take a moment to think about the situation. Think about the consequences should that be the case for your car and engine.

Kudos for you for thinking about taking the HP tuners course. That will help you understand more of the tables and the effect of adjustments. Be aware they will also tell you to log via wideband. It is tuning 101.

BTW The point of getting it on a dyno is to provide data during different throttle openings and load. Logging whilst doing so gives you a starting point to tune from. Requires wideband. Allows you to not have to do street pulls and runs, thus avoiding tickets

Lastly , IIRC there are tuners out there that specialize in the transmission tuning for MB. However, be aware the engine ECU and tranny ecu are interactive and adaptive. ​​​​​​​

Chevota

AFR is good per my wide band sensors. Fuel is easy to dial in.
My point on the tuning class is I will never pay for that. Even if I did I bet $ it wont cover Benz, which are different.
The tranny computer can be sent out to be programmed, but there is almost nothing I can do. I dont believe I'll be doing all that work, paying >$1800 and waiting a week + for the return of something I still wont like. I want to do it and program it how I want it, which will be different than theirs.
I've also never had one adapt that I can tell. Meaning resetting adaptations does nothing, but like a fool I try a couple times a year. I can force it to the most aggressive setting, but the bennies are minimal and it amplifies some of the negatives making it an overall fail imo. I miss mechanical trannys, they actually do what is asked and can be dialed in however you want.
Dyno time would be awesome if I only needed it for a hour or so. Maybe one day, but It would be waste right now. If the car didnt have the issue it has I could probably dial it in in a couple hours, on the street at 4am. Tuning with a mystery issue is another story. Like how I had it close but now it goes into limp mode. Even milder tunes = limp now. So is it related? A new problem? That's all part of the mystery.

WRC-LVR

Re fuel trims explanation for those who are following and want to understand STFT and LTFT :

WRC-LVR

"Tuning with a mystery issue is another story. Like how I had it close but now it goes into limp mode. Even milder tunes = limp now. So is it related? A new problem? That's all part of the mystery."

Limp mode is caused by many things. You have made lots of changes to the ECU. If for example there is a table limiting the torque value at a certain rpm and you exceed it by making other changes in the ECU, it may send the car into limp mode to protect the tranny and engine. Cause and effect, buddy

I always found that saving copies of the ROM ECU BEFORE making any changes allows to you go back if the change produced unwanted issues or effect. Make one change at a time. Test , rinse repeat

I would hope you are doing that?

Chevota

I did backup, but that includes the glitch, if thats what it is. Oem 0-60 is supposed to be 4.8 sec, but so far 5 sec is my best. Any mods to make more power end up in limp mode.
Below is most of torque related things that affect power, but I only know what a few of them do. And apparently many work together so if you change the wrong thing or make the wrong change to it, limp mode. Or increasing the value may lower power. And dont expect the name to be descriptive, they might as well say item 1, 2 etc. And the values in them dont make sense either. And the program doesnt show you everything, but what isnt it showing? Something I need to change? Who knows.

Wheel Torque vs VSS
Vehicle Mass Max Tq
Max % Torque vs RPM
Testing Max Tq
Torque Monitor Maximum
Max Torque in Emergency Mode
Indicated Torque Limits
Optimum Engine Torque (Monitoring)
Internal Torque Max
Normalized Torque

WRC-LVR

i fully agree, that is the issue with using "generic" logging and editing programs; table names are not correct, nor are the tables well defined, Additionally, the affect from changing values in a table is unknown. With MB it also interacts with the transmission ECU .

IIRc you have the OEtuning rom that you bought. Have you tried to compare tables to the OEM? It might just lead you to what tables OE changed, limiting your choices to those. Might also start to make sense in a cohesive manner too.

Did the link to the fuel trims video help you to understand what may be happening in terms the trims you have collected ? You might be able to adjust the fueling tables ONLY to see what effects that has. one change at a time, my man !!

PS i noted you said you are logging widebands o2 sensors...For the sake of others looking and learning, can you share where you have those installed and what brand/type?

WRC-LVR

Just to update this thread, many wideband O2 sensors use the LSU or Bosch 4.9 sensors in the exhaust stream. For turbo cars, usual location is post turbo 12- 18 inches as best located, installed in the vertical position but pre cat

Chevota

I know I answered this like 5+ days ago but I guess it didn't take.

Post 42 shows my exhaust. I assume Bosch, vertical, ~18" after turbos.
I tried to buy a couple O2 sensors from Vivid Racing ~5 days ago, but shipping for two sensors was $1019. No, not a typo. They didn't respond to my query about it but I see they raised the price of the sensors way up. The only other source with a reasonable price now only has one sensor in stock. Thanks Vivid... Review after review of Vivid says that place sux.
Like torque or anything else, you can only ask it to do something, and A/F is no different. It usually hovers around what I ask, but a bit leaner. Oem is set to run no richer that .9 lambda at the extreme, but usually ~.95 at full throttle.
I'm set to .875 to ~.830 at the extreme. Plus it starts to richen at lower rpm and lower loads.

Comparing the OE to oem files was the first thing I did. I also compared to many other tunes for 550's and 63's. Despite making a ton of changes variations, I still haven't been able to break 0-60 in 5sec.
There's some stuff in there you're not supposed to touch, but I think that is what's limiting me. Very confusing and next to zero info on the subject, but maybe next week I'll tinker with them and see what happens.
It's just frustrating to spend hours making a few tunes only to find out they all fail right away. And loading a new on the road is usually a pita. Even at home it's not easy. You have to beg for permission from HP to use the program, then beg again to load it. On the road that means hotspot via my phone, but cell service isn't that great where I am so sometimes I give up and install my other ECU, drive home or to a better area, try again. For $700 I think that's BS. It should let me do it whenever I want, period.

Yes, the vid was helpful. I assumed long term was the avg of short, but instead it's basically the course adjustment and short is fine.
Per HP Tuner it says the ecu doesn't calculate long term until the water temp is >212F, which I thought was weird, so I changed it to 200F but still get the same value. I then noticed that it calculates regardless of temp. In fact, it calcs before the O2 sensor is working. short term is 0 and lambda 1.00 while the sensors warms up, but long term is busy adjusting.
Between that and my excellent mpg, I think it's simply bs. Maybe skewed by the same issue causing my power loss.

WRC-LVR

I am including a link to how wideband Q2 sensors operate and the typical output range they employ to send to the auxiliary gauge(s). This is to help those folks following to understand how both types of sensors operate and some of the reasons they fail.

https://www.aa1car.com/library/wraf.htm

Most of the available wideband sensors output 0-5 V. corresponding to a 10.0-19.0 air fuel mix (AFR ) i have seen some that output 0-4 V, though.
Some common sensor /gauge manufacturers are : AEM, PLX, Innovate motorsports, Autometer Prosport etc Usually includes a Bosch or other wideband sensor in the kits

For those cars factory equipped to use narrow band o2 sensors, you can't just replace those with wideband UNLESS you modify the actual code, tables and other routines in the ECU. Widebands are usually added in the exhaust stream after the manifold but before any cat or pre cat and output to a gauge or to logging software on a laptop or other computer or even tablet. Requires drilling a hole in the correct orientation, welding in the mounting flange.

When using logging software, the software will need to know the output range of the sensor and the formula for converting the voltage into an accurate AFR ratio so it can be logged properly.

Some dyno operator or tuners use an exhaust type probe placed into the end of the exhaust. This works sub-optimally as the catalytic converter has changed the exhaust makeup by that point.

For the MB M278 engine, each exhaust stream will require one sensor and the subsequent logging of the data,

For racing applications, on certain engines that the AFR mix into 1 or more cylinders is constrained by sub-optimal flow of the air /fuel mix, installing o2 sensors on each exhaust manifold runner might be required but can be subject to rapid degradation due to heat in the exhaust close to the head(s)

Siegmann

What is your manifold pressure reading at idle?

Chevota

4-5 psia

Chevota

WRC-LVR - Since I can't post a pix in a PM, here's my options for O2 monitoring. The highlighted are what I'm monitoring

WRC-LVR

What is the voltage range on the 2 SAE O2 sensors? IIR you can edit the math on those. 0-5 v = WB voltage range corresponding to 10-19 AFR ? If voltage range is only 0-1 v then those are narrow band O2 sensors.
Also The 2 WB EQ ratio 1 and 5 does that use the output from the 2 O2 Voltage outputs. ? Just curious.

OT but one of the F1 teams uses HP tuners as a sponsor. gotta be doing something right !

Chevota

The OEM are .7 to .8 but in the extreme 0 to .93.
The Lambda are just that, lambda and no voltage reading to look at.
The Current I forget, just that it was useless to me.

I'm getting more and more power as I tinker but it's not easy at all with this program. No instructions, no clue what most things actually do and many don't do what they say or simply don't work at all.
It's also incapable of controlling the boost except on an extremely crude level, It's supposed to be able to control it better but that function simply doesn't work at all. So I may be forced to make the independent circuit I was going to make and cross my fingers all that work doesn't trip limp mode. Limp mode is killin me, and may actually kill me one day. It did it to me on the freeway last week, in the fast lane and no shoulder. I was super lucky and managed to coast to the far right in time because most of the time traffic is too thick to pull that off. Such a stupid feature to kill the engine. At the very least allow enough power to safely pull over! I programmed in ~6x the normal limp mode power but it doesn't help. My limp mode shut downs are not like a normal limp mode, it's basically equal to throwing into neutral. Actually I could probably drive it further if I put it in neutral. Then to un-Fu# it I have to have internet because you have to beg HP Tuners for permission to use the program, then permission to program the car.
So HP may be doing some things right for the big 3, but not so much for MB. Sponsorship means only one thing to me; the car owner/team is saying "I accepted $ from these people in exchange for advertising their product". Slick 50 sponsored too.