There may be more than one problem.
For the CG water source, see if you can borrow a pressure regulator. Once connected, if the CG water pressure is at least 40 PSI the incoming pressure is okay. Next to check is the water filter. Do you have a whole camper water filter? If so, the filter could be clogged. Also, if you are running with a 1/2" diameter fresh water hose, consider getting a larger diameter hose.
For low pressure on the internal pump, it could be the pump needs to be upgraded. Most RVs have a 2.7 GPM pump from the factory. I changed mine to a 4.0 GPM pump. That works fine with multiple faucets drawing water. There should not be a water filter between your internal pump and the faucets. Double check this.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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