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17 psig per the app, but I don't think the car compares it to ambient so it should shoot for xx psia regardless of ambient. My ambient is between sea level and 14.4psi. Anyway, that 17 is for a very brief moment, maybe 250ms which exists only because it takes that long to open the wastegates. Plus I have to do it just right to get that #, otherwise it's like you see in the graph. The point was it's a clue that shows the turbos work and there are no leaks, otherwise that can't happen. And 17 was with the tune. Without the tune it opens the wastegates too quickly and a high peak is <10, which again was for a small fraction of a second, then back to <8.
Oem or tuned, all vitals look perfectly fine except boost. Tuned boost is supposed to be 18, but I get 12. More like 11 or less if you average it, but I call it 12.
Basically, picture someone going in while you were asleep and programming your boost to be 5 psi low, tune or not. This is, imo, exactly the problem except nobody did it, it just happened. Glitch, soft limp mode, who knows. So everything is fine, except that one very important thing.
All shifts are at ~6000 if floored. 0-60 has been as low as 5 sec with the tune on a cold 5am morning. Not sure what it is without, but no doubt >6. 0-60 runs are not easy due to traffic so I never bothered to check oem.
The tranny seems to be working as it's supposed to. I have shifted early to see if it helps, but only when it ran correctly. Considering the low-mid torque peak is gone, there is no point now.
The boost shows on Xentry, but unless Xentry holds the MB mechs hand and tells them what the problem is, they can't help. They did not check boost psi when they had it, but I did tell them what is was.
People that have dyno'd these cars claim the advertised power is very conservative and actual is more like 440. I don't know and unfortunately this problem appeared before I used an app. Also, I don't what it weighs so I just plugged in a #. I think I used 4400 to account for me in it. I'm ok with an estimate, it's more about looking for changes. Plus the numbers are not accurate anyway, the Tq and HP don't add up, which I noticed first thing. Since the HP & Tq doesn't slow the data down, I leave it in, otherwise I'd remove it. I can assure you I don't need an app to tell me if it's low because when it worked right the difference was day and night. Before this I had an E350 and I believe the 350 would take it. With the tune removed the 350 would kill it. The 550 is heavier and has less power, simple as that.
Fyi the power doesn't follow boost in a linear fashion, it seems each psi nets more power than the last psi. For example, 0 psi and 4 psi I can't even tell the difference and have to use the app to tell me which it is. 4-8 I can tell, but it's not much. 8-12 is obvious. The oem boost to tuned, which is apparently 13 to 18, is far beyond obvious and could be considered violent. It's a bigger difference than 0-12 is.
Ok so after deciphering your extremely long wandering post, it appears that on both tunes the wastegates are opening very quickly not allowing the turbos to hold the peak it seems to maybe reach...
.Before i make a long post, have you checked the charge hose clamps? OEM ones are notorious for not holding much pressure. t-bolt clamps of the correct size can be used to hold the hoses on up to 50 psig. Many types of systems may also replace the charge air clamps
Since it happens on both tunes, then i would surmise 2 reasons. 1. wastegates 2. control systems
1. as mentioned before, you will have check the wastegates them selves. Most have an internal spring to hold them closed, if weakened, the wastegates will blow open early
2. solenoids usually control the amount of air going to the wastegates to help hold them shut or control the amount of opening if you will, it is a balancing act between the turbo blowing open the waste gate and the boost source air adding to the wastegate helping to keep it shut.
So in the case of 1. see if there is an adjustment on the waste gate rods. Check the amount of pre load against the factory specs. Adjust very carefully to specs as you dont want to overboost
In the case of 2. which i think is more likely, check the lines going to the solenoids from the turbo ( which is usually the source of the air signal to the solenoids ) If easy to get to , replace with high quality lines ( not silicone as that is slightly permeable to air ) and zip tie all connections so ensure no leaks.
Test the solenoids by applying voltage or controlling using Xentry. Make sure that they open and can actually pass air freely when they do. Usually they operate on a frequency basis 100% meaning they are open 100 % of the time passing source air to the wastegates. 0% meaning they are closed and not helping control the boost.
It is possible that the tables controlling the boost solenoids, the desired boost targets, the hysteresis of the control systems or the internal components of the ECU that control the solenoids are not functioning as designed.
Since it worked to start with for 2 years on the non OEM tune, and then slowly stared to degrade, I would think the most likely cause is a boost leak/solenoid line leak /wastegate internal spring issue.
I have been working on Turbo cars since 2005 and would share that those types of issues and fixes are most common. I used to do a boost test on my 2005 Evo MR twice a year. Amazing what a tiny leak will cause. Wastegates also go bad and get rusty inside not allowing them to use the boost source air to help control the waste gate opening.
Ouch. I will try to be more clear and specific. Thanks for bearing with me.
The picture explains my setup much better than my drivel. The turbo in the picture is the same as mine. The other is a screen grab showing the whole wastegate actuation system, which is not my exact system but basically identical.
Yes, duty cycle/pulse width modulation (PWM), just as described in the picture.
The only spring is in the diaphragm, which as you can see holds the wastegates open. Then of course vacuum closes them.
Boost/power didn't slowly degrade, it happened suddenly one day. I floor it daily so I knew right away.
All the lines hold vacuum and the Brake Boost Pump is at ~28" vacuum. The wastegates open and close as expected when you apply vacuum and release.
I also actuated via Xentry. The MB Dealer did all this as well.
I took it a few steps further and checked vacuum under boost to ensure the manifold pressure wasn't back feeding, but it remains at ~28" no matter what, which was measured at the vacuum port on the solenoid.
Then I checked vacuum at the line exiting the solenoid leading to the turbos, which is ~15". When it hits the 8psi boost mark it drops to 0" instantly. It will then vary from 0 to 15" as the PWM changes to maintain boost.
I can only assume the 15" vac is due to the PWM never being zero, but something like 5% minimum. So it's letting air in all the time and apparently 15" is what it ends up at.
I can't reach all the hose clamps, but I can get creative with tools to push on them and they seem tight. I'm not worried about leakage because if a leak was causing the loss then the wastegates would never be commanded open. Plus loading the tune would not change the pressure, but it does.
The replacement solenoid I bought changed nothing. It works exactly like the original. They both open/close as expected and the ambient air and vacuum source ports flip flop between open/closed and neither port leaks when closed.
So unless I missed something, my only conclusion is the ECU is commanding this to happen.
thanks for the pics, I dug into the control systems further and found that the turbos wastegates are vacuum controlled via a vacuum pump and accumulater.
See this link for a similar issue to what you are seeing.
Clip Here are some technical details of the boost control system on the M278 engine. Firstly, it is a bi-turbo V8 engine where both turbochargers are fed via exhaust manifolds on their respective sides. The turbochargers use vacuum generated by a vacuum pump and a reservoir to control the wastegate actuators. The vacuum is supplied via one boost pressure transducer that is duty cycle controlled and tees off to both boost control actuators on turbochargers. With manifold vacuum supplied, the wastegates are both closed via the wastegate control actuators generating boost pressure. If a vacuum leak occurs or the engine management control module wants to reduce power output, the vacuum is released and spring pressure in the wastegate control actuators opens up the wastegates. Clip
Note NO codes found under normal Xentry diagnosis
My apologies, 99% of turbo systems use a wastegate with a spring that holds pressure against the flapper keeping it from opening. The diaphragm admits turbo sourced air to control the boost as the waste gate starts to open by helping keep it closed. Solenoids control how much turbo air goes to the diaphragm. Solenoids under control from ECU tables. So the turbo spools up quickly, as boost reaches whatever the spring will allow, then turbo air is added to continue to help boost build. Allows up to 3-4 bar boost.
I can see lots of issues with the MB system , including vacuum pump issues, accumulator issues, plumbing issues, in addition to the solenoid issue and control over said solenoids
Read further on ...One of the turbos was not putting out the correct psi, due to a flapper issue.
May require disassembly to check if either has a problem with their wastegate flappers. Before that, I would check the vacuum pump to see if it can pull what ever the specs say. Also check the accumulator to see if it can actually hold the vacuum or the canister has a leak ( crack maybe ) . also by definition you will have to check the vacuum hoses (after the single solenoid ) going to both wastegates on turbos.
Not sure how the ECU looks at the picture but if it reads the O2 sensor on both sides for AFR, it is gonna realize one side isnt boosting the same and cuts vacuum which as seen above cuts it to BOTH sides = big drop in power
First off, thank you for taking the time to look into this and reply! It is appreciated
I found that article in the past but I don't believe it applies to me since I can make boost. In that example I'd imagine the ECU never commanded the wastegates open, because why would it. Mine does command them open because they can make boost.
I have yet to find anything online that was of help. I've found a few people with E550's that have the same issue, but they don't seem to care enough to look into it so they're ok with the low boost. Who knows if they have my exact issue or not, just that they have low boost.
There is no accumulator for vacuum, but I did install one to see if it would make a differences. It did not, which I knew before I started, but I had literally run out of things to try.
Remember, the control solenoid sees 28" vacuum no matter what, and I measured that right at the control solenoid. So it has all the vacuum it could possibly have at all times. I'd imagine this is why they left the accumulator out since there's no point.
The turbo side of the vacuum line, just after the solenoid, is 15" vacuum and it stays at 15 while at idle or cruise etc as long as the throttle isn't moving. When I push the throttle, even a little bit, it's first response is to vent and vacuum drops to anywhere from 10" to 0 depending on how long it vented for, and that is determined by how quick I push the throttle and by how far I push it. So just a little push on the gas it'll drop to 10, and quickly going to half throttle it'll drop to 0. This drop is just for a split second, then it returns to 15". Maybe it's to prevent ping, like how timing does the same thing on most cars I've checked, but opening the wategates just seems stupid. Maybe an emission thing, I just don't know.
Once back at 15" it'll stay there until 8psi boost is reached, which is anywhere from a half second to a couple seconds. At that point it reacts in a similar way and drops to between 10 and 0" depending on how fast it reached 8psi. So if it was quick, it drops to 0, if boost pressure built up slowly then it only drops to 10". From there it modulates to maintain 8psi which is usually in the 10 to 5" range depending on rpm and throttle.
So the wastegates are clearly being commanded open to maintain 8psi boost, and only the ECU can do that. The question is why? Did it glitch and now it thinks this is the correct psi, or is there some other reason telling it to reduce boost? I'm hoping the ECU alone is doing this, that way the replacement ECU will fix it. If some other mystery device is telling the ECU to do this, then the replacement ECU will do the same thing and I'll be worse off than before.
Both turbos dump into the same intercooler, single throttle and open intake, so the cylinders and O2 sensors on each side will see the same thing no matter what.
Frustrating huh? Imagine how I feel... Fyi I tend to have issues that nobody has ever heard of, so it's no surprise to me that this is not any of the usual problems. I had two other MB's that had issues nobody ever heard of and those were never fixed either. I had to sell one as a parts car and the other was in an accident and luckily totaled. I really don't want to get rid of this car, which took me years to find exactly what I wanted.
Get Konigstiger to pull the pdf of the turbo and wastegate control systems for your vin.
I,m willing to help but would prefer to do this offline. PM me to discuss options. My sister has a 2013 S550 and I'm gathering as much knowledge as I can in case i have to remote diagnose it
I sent a PM to him.
Fyi, the 15" vac I mentioned after the solenoid is for the new replacement I bought. The oem unit is much higher, I think 24"? But it changes nothing, the ECU commands whatever is needed to maintain the low boost.
They are both the same part # Pierberg made in Germany, with the Mercedes emblem. The cover over the air vent is different looking but they're no doubt several years apart so probably just cosmetic.
Maximum boost is 0.9 bar for the M-278 engine acc to manual. That is 13 psi.
See the attached explanation of the boost control system. ~ 8 items have input to the ECU to determine load, boost, and the control over it. The data is fed in to the ECU and read against a load table. The resulting signal are then sent out the boost control activation solenoid. Hysteresis is provided in real time from the sensors. Other factors that increase or decrease the load calculation and target boost will be engine coolant temp, ecu control over the throttle by wire and several others, including the pressure sensors pre and post turbos
Maximum torque of ~ 700nM is available as low as 1750 rpm. the manual shows the curve is flat to 3500 then tapers off sharply. Engine is rated at 320 kW and 700nM torque ( ~ 430 hP 516 lb/ft )
Hope this helps to give a better picture of the controll systems and allow better troubleshooting in case of issues.
WRC-LVR; I didn't know that's what you were after, I already have that pdf. And yes, I knew all that stuff, but thank you.
All those sensors etc work normally and throttle position, eng and air temp, octane etc make zero difference. In fact, nothing makes any difference.
Yesterday I swapped out the ECU with a cloned version of mine, no change... I was hoping it would just copy the security info over so it would start my car, but it appears to have copied everything over so if there was a software glitch I can only assume it copied that too. So all that trouble and no closer to finding my issue. At least now I have an ECU to tinker with.
So I guess my only options are to change the boost pressure in the ECU, if I can, or make my own circuit and bypass the ECU.
WRC-LVR; I didn't know that's what you were after, I already have that pdf. And yes, I knew all that stuff, but thank you.
All those sensors etc work normally and throttle position, eng and air temp, octane etc make zero difference. In fact, nothing makes any difference.
Yesterday I swapped out the ECU with a cloned version of mine, no change... I was hoping it would just copy the security info over so it would start my car, but it appears to have copied everything over so if there was a software glitch I can only assume it copied that too. So all that trouble and no closer to finding my issue. At least now I have an ECU to tinker with.
So I guess my only options are to change the boost pressure in the ECU, if I can, or make my own circuit and bypass the ECU.
Changing boost pressure in ECU wont help if there is a software glitch in the ECU control routines. Hysteresis control will still be same.
Sure you can make your own circuit. Just run the vacuum pump directly to the wastegates. There wont be any hysteresis over the turbos then unless the ECU tells the vacuum pump to shut off as absolute fail safe. Be very careful, Runaway boost wont be nice to the engine.
I meant an electronic circuit, to control the oem vacuum solenoid. Simple proportional control, boost psi controls PWM. Should work much better than the oem setup.
My circuit would have zero hysteresis, and it'll be much faster than the ECU (Electronic Clusterfuc# Unit).
Judging by the vacuum control to the turbos now, I'd say hysteresis is huge. Hard to tell most of the time with the throttle closing on me and shifting, but in a steady pull through 4th gear it seems to drive to a certain point in two or three very course jumps, then simply stops. I assume after it stops it's letting the light tension on the wastegates self regulate via exhaust pressure.
If I hooked vacuum direct to the turbos I'm sure my intercooler and intake would both rupture in about 2 seconds after I floored it. This is why I've never bypassed the solenoid as a test. The vacuum pump is just a classic brake booster pump, no safety.
I could do a mechanical control setup, but it would be much slower to respond and more difficult to adjust. I may add one as a fail safe set to a higher psi.
To change the boost in the ECU I was going to use HP Tune, which should arrive this week. It was $pendy so I waited to see if the ECU swap failed. From what I read you have to adjust a few things other than boost, like torque limits, but other people have done it so know it can. The HP Tune comes with some nice software that appears to be much better than Torque Pro or Xentry for monitoring and recording data. It still has to go through the CAN Bus so I'm stuck with that molasses speed, and maybe Bluetooth on top of that, but fingers crossed it works via USB.
I had a thought... have you logged knock parameters or the final knock calculation? The engine does have a knock sensor. If it is starting to be faulty or sensing feedback or other metallic sounds that match the frequency of knock the ECU is programmed to listen for, then the ECu will take that and cut boost, timing, shut DBW throttle etc, exactly what it seems to be doing.
I read on one of the other MB sub-forums the knock sensor was picking up sounds from the transmission, causing drop in boost. At least one other person on another MB forum reported the knock issue was an exhaust rattle against the frame caused by an ill fitting aftermarket exhaust.
Just saying......my opinion is find the root cause first
Commendable to make your own circuit. Also very commendable to dig into the tables on the ECU. That will be well worth it and im sure the forum will be better for it..
I did that on my EVO, there is about 100 different tables sub routines etc controlling the engine output for that beast. That doesnt include the AWD system control, separate ECU for that along with accelerometers ( X, Y, Z )
If the root cause is else where, such as the wastegates, vacuum pump, knock sensor, the other sensors such as the MAF or MAP, faulty DBW throttle body, you will have a convoluted problem, worse than you have now as the 2 system will conflict with each other.
Hi there ,
I had a C180 which had a similar issue until some one asked me to split the exhaust pipe joints and separate at all the boxes and check if there was anything in the box blocking the exhaust fumes, i did that to my surprise one of the boxes was full of white molecules cubes produced in the exhaust fumes , i was told by an experienced person that these molecules was the result of using cheaper fuel/gas ,I changed the box and the problem was resolved. I have since changed to C200 Wagon2005 and have mostly re-fuelled from Shell garages only where ever possible, I wish you good luck.
Hi my name is Pravinlal
i have got c200 Avantgarde 2005 recently the front seat belt sign has come up even if the belts are securely clipped into position, any clue to sort out the problem is appriciated,. My appologies for any mistakes as im not good with the laptop or computers thanking you.
Are there any TSB regarding the knock sensor on the 2016 e550 M278 engine ? Or possible incorrect coding on the ECU software interpreting the signals from that knock sensor.
Oh yes that really helps out. Esp the location on the engine. In that thread you added, it gives a lot of troubleshooting and Xentry results. ( some of which are confusing as to display.
Chevota, Check those out and the above diagrams. Also the attached cleaning of the Pierburg solenoid. Note above troubleshooting failure showed no initial Fault codes. Not meeting boost target did show up later !!!!
underlying cause is the vacuum solenoid not working well, leading to rapid cycling of the wastegate flappers leading to bushing wear on the flapper actuating arm = flapper off axis and unable to close properly to allow boost to build properly.
Cure: replace solenoid, check all lines leading to and from it, R an R as necessary. Check flapper arms for play going into turbo housings. up / down side play will require the turbo to be pulled and either R n R for bushing/ actuator rod /flapper or replace turbo
The video above is mine, he already stated is not his solenoid. At idle after the vacuum pump, but before the solenoid should generate 24psi of vacuum. Same on the solenoid at the connection between the y splitter for the wastegates. I also created vacuum by plugging my Mityvac pump into the y connector of the wastegates, and pumped up to 24-25psi, it should hold with 0 loss. The last one can be done with the car off.
The video above is mine, he already stated is not his solenoid. At idle after the vacuum pump, but before the solenoid should generate 24psi of vacuum. Same on the solenoid at the connection between the y splitter for the wastegates. I also created vacuum by plugging my Mityvac pump into the y connector of the wastegates, and pumped up to 24-25psi, it should hold with 0 loss. The last one can be done with the car off.
He doesnt get the correct vacuum after the solenoid. He's only getting 15psi. NOTE in post 1 he has no codes at all. " I sent a PM to him. Fyi, the 15" vac I mentioned after the solenoid is for the new replacement I bought. The oem unit is much higher, I think 24"? But it changes nothing, the ECU commands whatever is needed to maintain the low boost."
First to me that Indicates a bad solenoid , wrong solenoid etc. Put the OEM back on since it passes 24 psi Second there may be a vacuum leak on the lines or at the wastegate on diaphragm(s). Third wastegate flapper issues not allowing proper boost . Fourth This all started with an OE tune he placed on the car. All of a sudden lost power after some months. He took tune off and power decreased even more. Fifth he has replaced the ECU and reflashed the OEM tune on to it. That rules out circuit issues in the ECU. No change ..he believes a software glitch has been copied over.
It is much more likely an issue on the mechanical side, I agree he should apply vacuum using a Mity vac hand pump and see if it holds with no loss. If it doesnt then find the leak. If it does then move on to the wastegate flappers. I can see the scenario where one is bad, not allowing boost to build, and the right /left bank sensors are gonna see that and shut down boost.
Lastly he indicated the DBW throttle opening at WOT never gets above 75% which is about what he sees in % power he has reported. He needs to diagnose a sticky throttle or maybe a bad TPS ( but no codes remember ).
He has not answered as to if he has logged the knock sensor "seeing " massive knock counts coinciding with the drops in boost during acceleration. As previously posted, if the knock sensor sends high knock counts to the ECU, it will reduce boost, shut throttle down and reduce timing and change fueling.
He doesnt get the correct vacuum after the solenoid. He's only getting 15psi. NOTE in post 1 he has no codes at all. " I sent a PM to him. Fyi, the 15" vac I mentioned after the solenoid is for the new replacement I bought. The oem unit is much higher, I think 24"? But it changes nothing, the ECU commands whatever is needed to maintain the low boost."
First to me that Indicates a bad solenoid , wrong solenoid etc. Put the OEM back on since it passes 24 psi Second there may be a vacuum leak on the lines or at the wastegate on diaphragm(s). Third wastegate flapper issues not allowing proper boost . Fourth This all started with an OE tune he placed on the car. All of a sudden lost power after some months. He took tune off and power decreased even more. Fifth he has replaced the ECU and reflashed the OEM tune on to it. That rules out circuit issues in the ECU. No change ..he believes a software glitch has been copied over.
It is much more likely an issue on the mechanical side, I agree he should apply vacuum using a Mity vac hand pump and see if it holds with no loss. If it doesnt then find the leak. If it does then move on to the wastegate flappers. I can see the scenario where one is bad, not allowing boost to build, and the right /left bank sensors are gonna see that and shut down boost.
Lastly he indicated the DBW throttle opening at WOT never gets above 75% which is about what he sees in % power he has reported. He needs to diagnose a sticky throttle or maybe a bad TPS ( but no codes remember ).
He has not answered as to if he has logged the knock sensor "seeing " massive knock counts coinciding with the drops in boost during acceleration. As previously posted, if the knock sensor sends high knock counts to the ECU, it will reduce boost, shut throttle down and reduce timing and change fueling.
The OP did not wanted to listen to the advise about the solenoid on post 20 "The dealer checked it too, and all the lines, which held." if he had not I would have told him, what I mentioned on my last post to check from the vacuum pump.
I don't think he understands, that the solenoids close the wastegates to ALLOW boost to increase. The failsafe mode of the solenoid is to allow the wastegastes to open to avoid from too much boost to be generated. And the PSI of vacuum from the pump to the wastegate should be 24PSI at idle RPM.
That was the mechanical side of troubleshooting.
The electronic side would be the boost pressure sensor, knock sensor, throttle position sensor, heck even the vehicle yaw, pitch, and steering sensors can tell the logic to pull boost. There is more, but I would be too tired to explain today.
Agreed. S.Madman.... You have a very good understanding of the boost solenoid and WG workings. I took the time to read as much as i could about it from MB and have a background of turbo cars for many years. Yes vacuum holds the WG shut to allow boost. on this engine. Without vacuum, WG opens and boost drops .
One of things I am trying to do here is post up as much accurate info as possible on the control system and troubleshooting for the turbos. That way other interested parties can investigate the various parts that might be causing issues on their cars.
It would probably be good to do fishbone or root cause, If this and then do this analysis....:-)
What do you think about starting a sticky that can be posted in this forum to help with that?
I would've replied sooner but I never rec'd notice there were posts You see, I don't just have issues with electronics in my cars, it's all electronics, which is why I have five laptops. Only two or three means I wouldn't have a working PC half the time, so five is enough to keep me going. Two work now, but neither are without issues.
I could go on and on about what mechanical parts I've checked, but the end result is the ECU is commanding the wastegates to open and maintain a low psi. That basically rules out most all the things people are thinking up, like leaks and wastegates.
So the question is, is it receiving a signal from something and lowering boost in response, or is it just a software glitch? Keep in mind this happened suddenly one day, with only 29k miles on it, not over time.
Also note it can make boost, for a moment via various ways I trick it, but it's useless because the ECU will simply continue commanding until it sees the boost it wants. So in short, the system is capable, the ECU is not allowing it.
I have checked knock timing retard, and there is some but it appear normal and is not enough to cause a power loss. At least not from the retard it says it's doing in direct response. The knock sensors, four of them, will retard a couple degrees here and there. I think 3.5 at peak? The total timing is all over the place, which I wonder about but it's still not enough to cause this kind of power loss. I tried adding octane boost once as a test, and while I didn't check the knock retard, I can say it did nothing for power.
The throttle position at 75% is in actual degrees of movement? I forget now because there are several throttle PID's and their values differ depending on which one is used and what my current software will allow, but I believe it was ~2 to 75 or 13 to 87 deg depending on PID. Whatever it was, the throttle itself opens normally as far as it can go, unless the ECU says otherwise, which is often. Even if it were limited to 75% open it could not drop power this low. I don't believe 75% would drop power at all to be honest.
Madman; thanks but I do fully understand the solenoid and how it all works with the turbos. I've even watched what vacuum is needed to hold xx boost and how the ECU responds to various conditions, including me trying to trick it. It's pointless to trick it btw, which is why my only fix may be bypassing the ECU altogether. I don't want to do that because it may respond some other way, like pulling timing to throttle. What I want is the the cause corrected but to do that I'd need to understand it why the ECU us deciding to drive to such a low psi. So far I've has zero luck...
Thank you everyone for helping me try to find the issue!! I know it's frustrating but I think it would be easier to forget all the usual and mechanical stuff.
Like I mentioned with the laptops, I not only have lots of issues with electronics, but I tend to have unique issues that nobody has ever heard of before.
I don't suppose anyone knows how to edit the software I pulled out of the ECU via KESS, which is basically KTAG. I know professional tuner edit that file, but I can't find what software they use.