I need your help; I drive a Golf 4 TDI with 180 horsepower.
My problem is that, since Thursday, my turbo is no longer making its usual sound. When I press the accelerator, I only hear a loud hissing sound, but there is no power... Can you help me???
I don't think your turbo has a problem. Just check the path of the pressure hoses from the turbocharger to the intercooler, and then from the intercooler to the intake manifold. There's likely a leak somewhere (it should be quite oily there) where all your pressurized air is escaping. It's also possible that your intercooler is leaking.