I have 02 prerunner v6. CEL came on, got it scanned came back po136. I replaced the rear sensor yesterday reset the computer and the light came back on after short time. I felt around for leaks in the exhaust and can feel pressure coming out where I installed the sensor. When I installed it and scraped off the old gasket which was deteriorated, a little of the actual exhaust where the sensor mounts came off so now the new gasket and sensor can't seal. Would this throw the CEL, Any ideas of how to seal this or any other ideas in general. Appreciate it.