Read my post fellas... what im saying is not a loss of back pressure, Im guessing an excess of back pressure in effect choking the motor causing it to be very tired and sluggish due to a pipe being bent...

Try this... drink something through a good straw, then put a bend in the straw and see if its still easy to drink from it.... Or think about a water hose, what happens when it gets a kink???

I rest my case.....