Q: Changed the oil sensor an the car sounds an drives fine but when i rev an take my foot off the gas oil psi drops almost to 0

Although there is some variance across engine types, minimum oil pressure at idle is typically fairly low to begin with, typically in the range of 4 to 10 PSI. If idle speed drops below normal, so will oil pressure. Gauge response and accuracy is important. If idle speed is normal and you suspect an oil pressure problem be sure the gauge you are using to perform tests is accurate on the low end. Based on what you are describing though, the low idle issue needs to be fully resolved first because engine speed determines the pressure and once the low idle is resolved, the oil pressure issue can be re-visited. If you request an engine diagnostic a certified Mechanic, dispatched by YourMechanic right to your location, will identify the root cause of the low idle and the get the issue resolved for you promptly, including a re-test of the oil pressure. If you have further questions or concerns, do not hesitate to re-contact YourMechanicas we are always here to help you. ,