I have weak pressure in a shower in an upstairs bathroom. I have great pressure in the tub but when I pull the water diverter from tub to shower the pressure is very weak in shower. I removed the shower head and still found poor water pressure even with the straight pipe. Thinking this is a blockage between tub and shower or a bad diverter. Thoughts?

Hi CS

If you cleared the shower head as the issue then assuming the diverter is NOT on the tub spout I'd suggest replacing the diverter spindle. When you remove the existing diverter spindle you could also remove the shower head again and run some water via a garden hose down the shower pipe to be sure there is no blockage... if all OK there install the diverter and the shower head and see if things are improved.

If the diverter is on the tub spout I would replace the tub spout with a new spout/diverter and see if that improves things.

Mark