Not sure either tranny or some sensor
My 99 Volvo was really sluggish when I got it an a few months into owning it sometimes it will not accelerate or rev. It will idle forward or backwards but it won’t go like my pedal isn’t doing anything when I press it. Unplugged TV e mass airflow sensor and i feel like it has its original power but it makes some nasty metal noises when I accelerate or when it shifts but it’s not jerky or a tough shift just noisy