I've been having the same issue as everyone here. Water flows fine without a k-cup. I've run so many keurig decalcification products through it I've lost count. After cleaning, it always seems to work fine for a few coffees then clogs up again. Needle is clear as well as one-way valve. For fun I pinched the overflow tube that leads back into to water reservoir and started a brew with a k-cup. Coffee instantly started to flow properly and I was able to get a full cup 1st try. Another brew without pinching and it's back to dribbling half cups. I've blocked the tube for now and it has been running fine for a few days. At least I know where to look when I have the time to take it apart.