1.4 TDI rough noise when accelerating
Hi everyone,
I recently bought a 2015 VW Polo 1.4 TDI (CUSA engine) with a failed turbo. I swapped out the turbo, and the car drives well now.
However, during the first test drive, I noticed a very rough engine noise and shaking under load. It only happens under load—when the car is standing and I rev the engine, it sounds completely fine. It is a bit hard to describe, but it sounds and feels like when you drive a car in a gear that is way too high, right before it stalls. It’s a very bassy vibration that you can feel throughout the whole car.
The power output feels normal, and as soon as the engine goes over 1900–2000 RPM, the noise and shaking disappears.
I know these engines are known for dual mass flywheel failures, but mine is completely silent at idle. I am also not sure if the previous owner already converted it to a single-mass flywheel. Maybe the SMF explains the vibration?
Does anyone here own this model and know if this behavior is normal, or has anyone experienced this specific issue before?
I appreciate any help or insights you have!