Haudi

Hi All, I'm pretty desperate already, would greatly appreciate, if anyone has any idea what could be causing this issue - basically my A6 3.0 BiTDI 320 ps has been accelerating very slowly from steady rpms to 2000. It takes like 2-3 seconds to reach 2000 RPM and afterwards when the big turbo takes over, no issues. The car was tuned with Stage 1 chiptuning to 410 hp 800 NM, however I have removed the tune as I though this could really be causing the issue.. The car is now DPF/Adblue off with DPF removed and back to stock software. Apparently the issue is still there.. I was advised to take off both turbos and send it for test, I did it and the response from the test service was that it looks like the previous owner of the car changed the Actuator of the small turbo, which led to some difference in the small turbo's operation, so they suspected the issue is coming from there, however after fixing the geometry and placing back the turbosystem apparently the issue does not come from there.. Next think we did was to isolate the EGR and check if there will be any difference - not really, still getting quite slowly from 800 to ~2000 RPM's while when testing one of my friend's A7 BiTDI 326 hp his directly jumps from start to 2k RPMS without hesitation.. There are no errors on the car, nothing comes on diagnostic, my tuner also looked the car on VCDS and can't seem to catch anything. We checked all vaccumm points for leak and can't find anything. Only thing I have reparied changed on the car apart from the turbo geometry calibration is replacing the Crankcase Ventilation System both filters and repairing 1 of the injectors and getting the other 5 checked. If you guys can recommend anything, I'd greatly appreciate it. Thank you in advance!!!

Hi, For anyone interested, update below on my issue with stuttering and very bad acceleration between 1000-2000 RPMS. The reason for my stuttering and slow acceleration between 1000 to 2000 RPMS is the small turbo not doing its job - due to clogged dpf sometime ago, seems like the small turbo was damaged and it cannot reach the bar pressure that it should hence the stuttering upon lightly pressing the accelerator when calmly driving and car is between 1000-1900 RPM. That’s what I was told, today they will tear it apart to look further. No error codes, cause the small turbo is still making some bar pressure but not as much as it should. Also clean your intake pipes, mine was as clean as new but still - first thing they did was to open and clean the intake pipe. Hope this helps for all interested! If you want further updates let me know, i’ll post.

Hi, I’m not sure what’s with mine but I did remove the DPF sometime ago as it was clogged. Anyway sometime ago I had the car mapped to Stage 1 409 ps 790 NM. I’ve called the mapper and he’ll be taking the car this Thursday to check what is causing this stutter upon pressing slightly the accelerator when calmly cruising on the highway. Along with that, I’ve noticed that the car responsiveness to full throttle from 0 km, when steady and the rpms climbing to 2000 is crazily slow. Tuner suspects vacuum issue but we’ll see. I’ll update you, once I know. After 2000 RPMS car is flying but until it builds those 2000 from steady it takes like 2-2.5 seconds 😂

Hi, did you manage to solve the issue? I am experiencing the exact same issue.. Thanks!