I have a customer with a 2007 5.7 mag Mercruiser with a Bravo 3. I have very little block pressure .3-.5 at idle and 6.0-7.0 at 2500. I have changed pressure sensor, impeller, pump, no bravoitus, bypassed the outdrive completely. Checked riser gaskets(Dry Joint) to make sure the gaskets were installed correctly with the right gasket. There is no popit valve on this engine. I checked thermostat and housing and all seems good. To me it seems like the water is flowing thru the engine to quickly? I checked the cooler and it is an open cooler with no baffles. I am getting the same reading on the rinda scan tool as well. Any Ideas would be greatly appreciated