The hot water pressure is not good throughout the entire house. The hot water tank was replaced last year. However, this problem just started about a couple of weeks ago.I have tried opening the pressure relief valve, shutting off the cold water and turning it back on, covering my hand over the hot and cold water tap and started to drain the pipe on my hot water tank. At first, a dark black color came out. Then I left it on until it cleared up. I shut it off and tried the spigots again. Still no water pressure. Any other suggestions? I check under the crawl space and noticed that the pressure part of the incoming cold water is leaking with a drip about every 2 seconds. I'm sorry, I do not know what it is called. It is the inline pressure attachment that gives the water the pressure it needs. Any suggestions as to what it could be? Thanks

Hot water starts at the water heater. Make sure all valves are in open position. Also, check for kinks in water heater supply line and properly installed nipples at the heater. Some nipples have back flow device built in. If not installed with the flow, they will cut down on water flow.

How is cold water throughout the house ? Any loss of pressure there ?

The device that drips is most likely Water Pressure Regulator and/or Pressure Relieve valve. If they drip than they have to be replaced.