Hello...
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I am hoping someone can help me. We installed a brand new dishwasher last week and now the kitchen faucet barely has any water pressure. It started fine, then we thought we heard a slight "klunk" a couple days later, and now there is barely any water pressure. The faucets in the bathroom work just fine. The pressure was excellent with the old dishwasher in place. What could we have done wrong to cause this?

It sounds like you have sediment blocking your faucet, it could be trapped in the sediment screen at the end of your faucet spout or trapped in the faucet valve itself, you didn't do anything wrong to cause this, just repacing the dishwasher line could have loosend some sediment build up in your pipes causing the problem. I would first check the sediment screen on the end of the faucet, and if that isn't the problem, shut off your supply and remove your valve assembly and clean it, this should solve your problem. Or if your faucet is a little out of date you could always use this as a reason to update your faucet.

Question: where is the water supply for DW connected to ?

For now, remove and clean your aerator. See if it helps. Back to you. Milo

I agree with Milo and Lilpoppa it sounds like you have sediment in your faucet and maybe just in screen of the Aerator see the image below remove it, try it without the aerator and see how is the flow, if it is good clean the screen and install, if not you tell us what is the brand and the model number of you faucet and we will tell you what the next step which will require to remove the cartridge or stem depends on your faucet, Thanks.

John