Hi.
We've got a 2011 RAV4 2.5L that's had the p0420 code for about two months now. The code came up after we replaced both sensors, downstream first then the upstream afterwards. We havent really driven the car that much, probably about 1k miles total in both months. But during the times we did drive it, all we have noticed is a MPG drop in our drives (because of running rich I'm assuming?).
That leads me to my question. How likely is it that it's actually the O2 sensor(s) that's still the problem for this code? We replaced the downstream sensor when the P0136 code came up. After about fifty miles, the same code came up again and then afterwards, we replaced the upstream sensor. After another fifty miles, the p0420 came up and no longer the P0136 code.
Furthermore, if it's likely that the CAT needs to be changed, will I be wrong with going OEM or is there another cheaper yet OEM quality aftermarket solution (i.e DENSO)?
Furthermore, I'd like to ask about some of the preventative maintenance we should start looking into. We've had the car since new, and it has about 126k miles on it now. We've replaced the spark plugs at about 120k miles, did rotors and pads just last month, front and back wheel bearings last month as well (thank you east coast shitty roads), as well as a full coolant flush about six months ago.
We're looking into doing a transmission fluid change as well. Any other thing that we should also do (that we can do in our garage)?
We've got a 2011 RAV4 2.5L that's had the p0420 code for about two months now. The code came up after we replaced both sensors, downstream first then the upstream afterwards. We havent really driven the car that much, probably about 1k miles total in both months. But during the times we did drive it, all we have noticed is a MPG drop in our drives (because of running rich I'm assuming?).
That leads me to my question. How likely is it that it's actually the O2 sensor(s) that's still the problem for this code? We replaced the downstream sensor when the P0136 code came up. After about fifty miles, the same code came up again and then afterwards, we replaced the upstream sensor. After another fifty miles, the p0420 came up and no longer the P0136 code.
Furthermore, if it's likely that the CAT needs to be changed, will I be wrong with going OEM or is there another cheaper yet OEM quality aftermarket solution (i.e DENSO)?
Furthermore, I'd like to ask about some of the preventative maintenance we should start looking into. We've had the car since new, and it has about 126k miles on it now. We've replaced the spark plugs at about 120k miles, did rotors and pads just last month, front and back wheel bearings last month as well (thank you east coast shitty roads), as well as a full coolant flush about six months ago.
We're looking into doing a transmission fluid change as well. Any other thing that we should also do (that we can do in our garage)?
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