I have a 15 year old Moen bath/shower combination faucet. I had to replace the cartridge due to a leak. Now I cannot get enough water to go to the shower head. When I pull the diverter in the faucet the water pressure seems to be too great for the diverter to work and I get just a dribble of water out of the shower head and a vast amount of water spewing past the diverter into the tub. I also changed the tub faucet thinking the diverter went bad. No such luck.

The cartridge is Moen #12801. Is it possible I could have this thing in backwards?

Bill

Did you check and see if there was anything left in the assembly before you put the new cartridge in (pcs of washer from the old one) take it back out and look down it with a flash light. If not it could be your diverter.