Service engine light came on at 41000 miles.
If you can afford a $150 scanner buy it. Then if you get a P0420. Check which bank; if it tells you bank 1 it's the firewall side if it says bank 2 it's the radiator side. Change the upstream sensor first, then you have to let the car run for about 30 miles highway until completes the 50 cycles so that it resets by itself. If you have more than 80000 miles it might be the catalytic. I have some experience in mechanic even though I'm a Computer engineer, and I found the problem. So I'm pretty sure you guys can do it too.
Nice troubleshooting advice. I am also a former mechanic, turned engineer (Electrical Engineer). I detest the new before and after catalytic converter oxygen sensors. There are also several other borderline useless OBDII nuances, which are equally as frustrating. That is what happens when elected officials try to stick their noses into technology. I personally do not care for the Japanese cars, but the Maxima is a nice machine. My parents have one in Infinity I30 trim (forget the year, but it is the last year before they converted over to the I35's). The check engine light just came on, so I will check for that problem.
Regards.
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