Guys,

My car is 100% stock.


While this is not MB cars, it is a good example on how "poor" tuning file which has capability to silence the DTC codes ( WITHOUT YOU KNOWING ) might someday cause you issue.
Something to think about .




Watch slowly and enjoy it........


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I know some of our car feature/s or operation/s, will NEVER run when and if there is a pending DTC on it.
Imagine an engine perimeter DTC, important one triggered but not reported ??


FLASHBACK
I remembered 15 years ago or so , when I was involved in paralleling/synchronization of 5 of 500Kva generator using 20kv transformer and fiber optic communication with PLC
Each generator is 1KM or so a part. They are part of a approx 4KM converyer belt system carrying coal from stock pile + crusher and then to the pier by the river.
The designer uses PLC and he needs to make a program on how the parallel/SYNCH power system ( load sharing & synchronization ) is supposed to operate.
Me dummy on such programming for PLC, I believed its called LADDER programming or something like that.
Anyway, there was 1 line on the program if I remember right was missing two of " ( apostrophe ) for a word/object.
The electrical parallel system could run, all 3 to 5 generators, but it wasn't very smart like how we wanted it.
Only on the second day after slowly tracing the program line by line the mistake was found and all 3 to 5 generators run so beautiful while being married/parallel/SYNCH

To those who does not understand electricity well, marrying two or more of 3 phase 230/400V AC electrical system ( generators ) is NOT easy like doing parallel for 2 or more 12V battery to get more amperage.
Accuracy of the frequency, 50 or 60 Hz need to be as good as 0.1 HZ or typically 3 RPM of the engine for 50/60 Hz unit.
1,500 RPM needs +3 RPM or 1,503 RPM accuracy, no joke. The electronic governor ( throttle control ) on these generators are so awesome.
50 Hz gerator at 1,500 RPM = 30 RPM per 1 Hz. 0.1Hz = 3 RPM.
60Hz generator at 1,800 RPM = 30 RPM per 1 Hz

Anyway, that was the moral of the story.... we do not know WHAT WE DO NOT KNOW , so it is good to learn from others.
.

 

I enjoy the DiagnoseDan videos. Pine Hollow Auto Diagnostics is another good show. using the same plastic tubing MB uses to cool its turbos as Renault does for fuel line seems a questionable choice.
had a flashback of my own when you mentioned coal conveyors. many moons ago, I was the warranty engineer for a chicago area gearbox manufacturer.
when the one way gearbox clutch fails on a one mile long conveyor full of coal that operates on a 30+ degree incline, it generates several phone calls.

 

Pine Hollow , I like Ivan...been watching him for years.
Royalty Auto Service is also good.
Dave's Auto Center is good for truck guys but his workshop mechanical/machining toys are nice.

30+ degree incline...dang that is a workload.

 

Excellent diagnosis and troubleshooting video.

I’m not a big fan of Autel. But I have also had problems with iCarsoft. I don’t think either uses LAUNCH software.

Notice in this case the tune was a custom tune and not off-the-shelf. I know OTS tunes are not optimal, but also I think they are a bit “safer”. So, I am willing to get very good performance instead of incredible performance. I also believe OTS tunes are less aggressive to mitigate liability. Also, a general tune is a one-time sunk cost for the tuner, allowing more profit on future sales.

I wonder, however, if he could have cleared the “non-existent” codes to see if the car would start. Too late now.

 

He can't clear the hidden DTC as it is not showing at all if there was indeed a DTC.........on the tuned version, that is the problem.

I came across Launch scanner telling me DTC which is not there, I mean even Xentry can't read/detect it. A stored DTC.
I forgot what the DTC was.

So even scanner can go banana too I guess...LOL

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Unless we can code ECU like a true Bosch/MB engineer, we best cross our fingers when getting a tune.
But if the tune is the cheater type, aka cheating sensors value, that is no good.

 

With MB. It’s pretty straightforward. Get a tune with Renntech or Kleemann and you will be fine. Never had an issue. I don’t use random companies that promise huge gains from N/A cars. A conservative tune should not harm your engine or various components. Also, many cars use no business being tuned and many people have no business tuning them.

 

That! 👆

 

I’m not sure how clearing codes works, such as if the control module is just reset or what. I know some scanners allow you to “clear” a module even if there are no DTCs, and some do not.

I know some tuners offer the option to disable CELs (usually for O2 sensor issues), but I have never chosen to do that. I know when tuning Audi/VWs, usually if it a fueling and boost adjustment to increase performance. However, when I got my tune from Vivid Racing, I was told that tuning a Mercedes is more complicated because engine torque is controlled (or something like that). However, the torque limiter is never disabled. And though the torque limiter can be disabled with the LAUNCH scanner, I do not recommend doing that.