Low power on your air impact wrench can be very frustrating and really slow down your productivity. Before you throw away a perfectly good air tool, there are a few things you should check that could easily correct the problem.
1.) Your impact wrench could have a dirty inlet Bushing or air strainer screen. To solve this problem, clean them with a suitable cleaning solution.
2.) Examine the cylinder. Replace it if it is worn or broken or
if the bore is scored or wavy.
3.) Disassemble tool and clean all parts with a suitable cleaning
solution, in a well–ventilated area. Reassemble the tool according to the impact wrench manual.