I spoke with my Director of maintenance services, he at one time worked in a motor shop. He said that a 2 hp 30 gallon air compressor is barely sufficient to handle the load of a 6 bay car wash. He said to take the motor to a motor shop and have the capacitor and the start switch checked, it’s more than likely the start switch on the back of the motor, it shouldn’t cost more $50 to have it repaired if it’s the start switch. Also check the pressure switch contacts, to see if they are burned. How old is this air compressor? We have a 2 hp 30 gallon air compressor at one of the washes that’s got to be 20 years old that’s still in service, running every day never a problem with it.