I'm sorry, but I/we have absolutely no idea what car you are working on. For all we know you could be lost and it's a Kia.
Why would you change the O2 sensor? Is there a code for it? Did it test bad?
If you want help you need to provide all the information on the car, including but not limited to aftermarket stuff and EVERYTHING you have done to troubleshoot this problem. If you can't do basic troubleshooting needed to find and fix this, I highly recommend to take it to a shop that can.
If you had searched, you would have found that P185 is for Fuel temp sensor so no replacing your coolant sensor will not fix this code.