Engine fault, repair needed?

Title says 230,000 miles but it's 230, 00K kilometers. About two months ago I've got this error on my display, and no other indicator turned on, like engine light or something, just this error, and the symptom is losing the boost power. The car will run just fine, and I've been driving it for a month with no issues, I just have no turbo, or whatever is giving my engine that boost when I press the gas pedal. Actually, when I turn the engine on and start driving it for the first 30-40 seconds, I do have boost, and I can reach 150KMph within 15 seconds, but then this error pops up and after that it's just "lame" mode. When I press the gas pedal, I can tell it’s working for the first 2-3 cm from the top, I can step on it down to the bottom and nothing, just the top of it will work and give fuel to the system. In idle mode when I press the gas pedal it will rev up over 4000 RPMs with no issues, it’s just when I shift that nothing will happen when I press the pedal going down after few centimeters. The first 30-40 seconds after I turn the engine on, and drive it, when I press the pedal to the bottom it’s working great. I took it to the first mechanic and he run diag on it and said it’s MAF sensor. I spent $180 for it and guess what, it wasn’t MAF. Then I took it to the second mechanic and he said the same, when I told him that I put the new MAF he stale and said well perhaps it’s turbo geometry. So I guess I would have to buy me a new turbo. Anyway, since then I took it to 4 other mechanics, and they all said the same. So, I assume there is some malfunction in the diagnostic software that these people download from wherever. I spent nights on the net looking for some answer and I can tell I do not have any symptom that people usually describe, or sites give as a reason for this. Engine is not hard to start, no smoke from the exhaust, no clicking, no leaking, no hissing, no dust, no fog, no steam, no jerking, no staling, no turning off in idle, no Santa Claus under my hood, no gremlin on my right mirror. I left it intentionally to run in idle for a few hours hopping it will turn off. Nothing. The car is running just fine. I spent aprox $200 for different additives hoping it will make some difference. This morning I bought EGR additive and sprayed it in the air system. That actually made some difference, for the first 5-6 sprays I could tell the engine would rev from 2000 rpm to 2500 rpm approximately 10 seconds after the additive reached the inside the system, and I could actually smell some burn coming out of the exhaust at the back of my car, but then after that I sprayed aprox a dozen sprays in different time intervals and nothing. You can tell the additive would boost the engine once you sprayed inside but that’s it. Afterward it’s just normal run. So I guess the “chimney” was a little bit clogged, not significantly, but yea, some “smoke” stuck on it somewhere. When I used EGR cleaner no weird smoke was coming out of my car’s “tail”. Waste of time, I spent money anyway. I didn’t notice any change in fuel consumption, not at all. So, I do not have any usual symptoms. Except... At first I didn't connect it with this because I thought it was my AC unit failing and there was no error on the display, but something like two months ago, I smelled inside the cabin something that I can describe like horse s***. I know, this is nowhere in the manual, but I was really trying to make it smell like rotten eggs, or expensive honey or something. No, no... That smelled like horse s***. Seriously. I thought it was bad air filter, but you see I serviced the car something like 6 months before that. Complete service, all filters, all belts, all liquids and everything. And even if it was air filter sucking something under my hood then I would be able to smell it when I pop up the hood. But under the hood there is no horse s***, just inside the car cabin. And I didn’t really paid attention until few days ago, I noticed that this error would pop up on my display right after I smell this horse beast coming out of my AC fan. For the first 30-40 seconds after I start the engine no smell at all, and remember boost is running just fine, but then once this smell starts coming inside the cabin this engine fault error will be displayed and I loose the boost power. The smell will last for like 4-5 seconds and then after that nothing. And it’s been like this for like two moths now. I’ve been driving car regularly. I also have to say that if I turn the AC off and turn the engine on there will be no smell inside the cabin nor under the hood, or around the car. The error will pop up regularly after 30-40 seconds, but there will be no smell at all until I turn on the AC. So, I suppose something is burning somewhere that has something to do with AC unit, even though I have no clue what AC has to do with this problem my car has. All the fuses are ok, all sensors are ok, everything seems just perfectly fine. I cleaned the DPF when I serviced the car so I suppose it has nothing to do with this, even though I spent some money for DPF additives since I started having this issue. As the matter of fact, the other day the engine was in repair mode for like 15 minutes, not engine fan but that repair loud noise when the horses are burned inside DPF, and I guess that part is working just fine. After all, a diagnostic software didn’t say anything about it, right.
I also have to mention that the first time this engine error appeared was after I drove 200 KM under Cruiser mode. I stopped, refueled, turned the engine on, and this error popped up. I tested the cruiser and the limiter number of times since then and Tempo is working under the perimeters. To put the strawberry on the top of this I also have to mention that this Horse smell appeared for the first time the very day I was about to Cruise on the highway.
So, AC, Cruiser and Turbo. If any advice is left somewhere in the bag...