I swear by the Kirby Shampoo system. My Grandmother has lovely blue variegated wall to wall carpet. For about 10 years it never saw a carpet cleaner. When I moved the sofa I could see what the carpet should look like, the rest of it had a brown hue. I did one shampoo with my Kirby and the carpet...
I had a Shark Navigator Lift Away that had a similar problem. After 6 months of constant use it would not suck. Turned out the motor was caked in fine clay dust (I live in red dirt Oklahoma). If it is under warranty I would contact Shark and have them fix it. Once it is fixed I would sell it and...