Loud Engine: Powerbox for More Power

'I've had a powerbox installed for a few days now, and I've noticed the following while driving on the highway. The engine is louder than before. Especially when it goes above 3000 rpm, it sounds like a heavily stressed gasoline engine (rumbling). Before, it was so quiet that you mostly only heard the wind and tire noise on the highway. It doesn't produce excessive smoke, and it doesn't go into limp mode. The only observation I've made is that it surges forward quite abruptly at 2000 rpm. It used to be much smoother.'

Could this be due to this specific part, or are there other potential causes that could result in a louder engine? By the way, this is a 90 hp TDI (VP) engine in a SEAT Leon.

Hello,

With a higher fuel injection volume, the noise level also increases slightly. However, this is hardly noticeable.
I would suspect loose parts in the engine compartment or mechanical contact between various components (due to the increased power, the engine might "rock" slightly more in its bearings during acceleration).

Best regards, Rainer.

Okay, so I adjusted the box slightly. Now the humming or booming seems to be gone. However, the performance isn't as powerful as it was before. I've heard something about 'torque rumble' in connection with chip tuning. Does that exist, and was that the effect I was experiencing?

Previously, it would run normally at full throttle and 1500 rpm, but then, starting at 2000 rpm, it would surge forward aggressively with two noticeable jerks. Are these jerks normal when using a tuning box, or do they indicate poor quality? By the way, the tuning box also intercepts the mass airflow sensor (MAF) signal.