This is a 2003 VW Touran 1.9 L TDI.
Basically I was starting to accelerate in 2nd gear when something popped in engine compartment and it lost power. Whenever I press on gas pedal in 1st gear, it just sucks air very loudly and keeps retching, lacking power. The only way to accelerate is by not pressing gas pedal and letting it accelerate on its own idle speeds, but as soon as acceleration pedal is pressed, it just keeps retching and doesn't really accelerate.
What might be the problem?