Volvo V70 P3 D5 AWD randomly shaking whole car while driving

Hi there. So This post is probaly aimed at more experienced people with volvos.

*Excuse my eng, not my native language but I will try

Okay so I have Volvo V70 P3 D5 AWD in automatic (about 312xxxkm). Past two years it was more in service than in my parking lot. The problems started with small defect, (they said it was stabilizer bars - front) and while checking, they found out that owner before us had the cylinders somehow edited to inject less diesel (so it saves fuel...smart guy). So they fixed the values to normal and then it started. So... The problem was and still is, that the car when driving , sometimes, basically randomly but usually after like at least 15mins of driving, the engine starts to have rought behavior, roughter sound and the most evident thing, the car start to shake for like 4-6 seconds.. like shake so much that it resonate some metal part right before the shaking stops, so this problem led to me bring the car multiple times to service (volvo certified, two different services). First they fixed the already existing cylinders and found out that one is nearly dead. So i was like.. good now i know whats the problem. It would have make sence that one cylinder was missing out sometime and it did the shaking. Anyway.. 55 km and the problem was back. So they checked the cylinders again, vida all clear, and they assumed that the EGR and DPF could have been problem.. Both new.. Boom didnt fix it.. actually again.. for few kms it was fine but then.. nope... So the technic guy told us that he needs some error to know..since the car doesnt say anything.. Basically he said, "Drive until it shows error". So.. I did.. After like 150kms we decided to try another service in different city since it was getting more frequent. So they immidietly said new cylinders..all of them... Funny thing, while driving to that service, bualah, orange icon "visit service,motor" Finnaly it showed error. After another two months waiting for Swedish parts, it was fixed, or so we thought. We were happy since it has cost fortune and it was stupid to not have this car for basically 1.5 years. Well.. It has been three months since the last service, they switched the cylinders and said that the cables for them are quite not in good shape too but it should be fine. Well, yesterday, I was like 18km on road when the car did that sh1t again. It shaked for 4 or so seconds, the fuel usage went up abit and it had louder noice of motor (: good.. You can imagine my sadness and anger . Well I tried to be optimistic, maybe its just that there was some "bad piece" in diesel? (living in europe, we all know the quality of diesel is getting worse rn).. like 1km and boom.. again.. even with the metal sound,..... the ride was like 28 km.. in those after the first time it happened twice again, on way home not once..it just had abit of roughter sound..but that can be bad diesel.. (Note that i am not using the sh1tiest diesel there is, its actually the "better"one, but not the premium one). No error, nothing else wrong with the car....... I do not know what to focus on right now.. like could it be the cables? Could it be turbo doing it?.....Or could it be oil? (i have to do oil anyways since its time based on km). It makes sence to be somewhere near motor. Its not happening while doing certain behavior and its impossible to recreate it on purpose. Its just completely random. I dont know.. ..it was fine for like 2000 km until now.. So.. please, do you have any advice about where to look.. did that happened to any of you?.... The car is overal in good shape and I dont want to give up on that car...Any help is more than welcome...Thank you

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