My compressor seems to work well, turning on as air is used. However, the first gauge always shows 80 psi, never getting up to the max. And, the second gauge always shows 0 psi, and I get low pressure at the hose. I get enough to blow debris, but barely enough to quickly fill a car tire. I don't use pneumatic tools. How do I adjust the device to deliver correct pressures? Also, can a gauge go bad, and should I replace it? Thanks, David B