I know they are both important in their own way, but between the upstream AF sensor and the downstream O2 sensor is one more important than the other in determining if your catalytic converter monitor will set or not?
After 2 weeks of trying the two major drive cycle patterns for my 2002 Toyota Sienna it's still a no-go on my cat. monitor setting.
I would think my evap system being funky and not setting might have something to do with that, but for the last two times (2 years apart) I was due for a smog check the evap did not set and the Cat. monitor did so I don't know why now that would affect the Cat. now, if it does.
My thought is that my sensors might be a little cruddy and so I was going to replace one or the other of them and somewhere in my head I got the impression that the downstream sensor was the most important. But exactly where that idea came from I can't say. I think I read it somewhere once, but when trying to search that it doesn't particularly come up....which brings me back here.
After 2 weeks of trying the two major drive cycle patterns for my 2002 Toyota Sienna it's still a no-go on my cat. monitor setting.
I would think my evap system being funky and not setting might have something to do with that, but for the last two times (2 years apart) I was due for a smog check the evap did not set and the Cat. monitor did so I don't know why now that would affect the Cat. now, if it does.
My thought is that my sensors might be a little cruddy and so I was going to replace one or the other of them and somewhere in my head I got the impression that the downstream sensor was the most important. But exactly where that idea came from I can't say. I think I read it somewhere once, but when trying to search that it doesn't particularly come up....which brings me back here.