I have the above dishwasher. The bottom of the dishwasher sprays good but the top is not working very well. I have checked and made sure the unit is clean and free from debree. I also made sure that the top rack (holds glasses) slides back and seals seats well (No leaks) when in operation. But I still do not have any water coming out of the top spreayer.

Trouble shooting - I have taken appart the bottom of the dishwasher to make sure there is no material obstructing flow.

I have turned on the dishwasher with the door open and the pump seems to be pumping. Not sure how much pressure should be coming out. The sprayer on the bottom rack seems to be working well.

- The tube on the back of the dishwasher funnels the water up to the top sprayer. The water is channeled through a seal that is mounted to the top rack. When the rack is pushed to the back, it seals off the water channel. This seems to be good but again, there is no pressure to get the top sprayer to work.

My question - How much pressure should be coming from the pump and how could I possibly check the pressure?
If the pump is pumping, maybe it does not have enough pressure to get to the top sprayer. I do not even see water coming out around the seal.

Have you seen this problem before and what is the most common reason?