Answered by Sidi Moustafa Elqabbany
If the odor of urine remains even after flowing water over it, is the garment still considered to be impure?
Answer:
Walaikum assalam,
When removing filth, you are required to wash until the taste, odor, and color disappear. If either the color or the odor remains after washing, scrubbing, and wringing three times with soap, then the garment is purified. If both the color and odor remain in the same spot, you must continue washing.
And Allah the Exalted knows best.
Moustafa Elqabbany