Water Gage goes to 160

If it in fact is ONLY getting to 160 degrees then it is likely not going to closed loop and fuel system is running rich because the coolant temp sensor sees only 160 degrees and may have fouled plugs causing misfire. You should be in the 195 to 205 temp range. Have it checked out with infrared temp gun to verify temp at thermostat housing and change the thermostat as needed.