P0420(yes I've googled)just some questions

[Amirocassar]

Hey guys so recently got code p0420 tonight after 30 minutes of driving with a new batch of gas. I went home looked it up and cleared it. Is it possible it's a bad batch of gas? I doubt it's my o2 sensors since I changed both in march. Praying it's not the cat and if it is I guess I'll try the simulator, but my question is how much in trouble can you get into if one were to find out you have them. I know it's unlikely but just hypothetically. I'm gonna look at the MAF( I heard someone cleaned there's and it went away) but again I cleaned that a couple months ago and it was filthy. I'm gonna see if it pops again. But any recommendations would be great. I'm praying it was just a bad batch of gas since it was at 10pm and who knows maybe it was crap gas. I put some Lucas fuel treatment that I usually put in to maybe help. I'm assuming it'll pop pretty quick again if it wasn't a fluke.

 

[snow junky]

your cats going bad,,, unless you have smog inspections no one will know you have a o2 sim

 

[thebrandon]

Realistically the only way for an inspector to know is to hook it up to the sniffer if that is required in your state, or if when you drive up to emissions you say, "I have an O2 simulator".

 

[AZ4Running]

Um no you can test a cat to see if it lighting. You need a lazer temp gun, get the motor to operating temp and check the temp of the cat on the inlet and outlet. Temp in should be way higher than temp out by like 200 degrees if its not and the temos are nearly the same in and out then the cat is bad.

 

[Riders of Lohan]

I have never had a "bad batch" of gas and I can't imagine the time of day you fill up would have any effect on how your car runs....


What kind of O2 sensors did u use?

 

[Amirocassar]

I have never had a "bad batch" of gas and I can't imagine the time of day you fill up would have any effect on how your car runs....


What kind of O2 sensors did u use?

Its not the time of day. But fuel in there tanks at the gas stations do settle so I was wondering if I got any contaminants. I cleared the code and it came back a week layer. I guess I'll just keep clearing. It didn't happen until this winter so I don't know if the cold could have anything to do with it. I just hope it was coincidental and it really is just the weather. To never have this happen and it happens the minute the weather goes negative made me wonder.(just being unrealistic for the sake of praying to save money lol).

 

[Amirocassar]

Realistically the only way for an inspector to know is to hook it up to the sniffer if that is required in your state, or if when you drive up to emissions you say, "I have an O2 simulator".

Yeah was just wondering. Since with my luck I'd get it and that's what would happen lol.

 

[kh02sport]

I battled this code for months in my 02. I cleaned the MAF, changed O2 sensors (both denso) new gas cap, plugs and wires, still no luck! Tried Seafoam and Cataclean. I came to point of the O2 simulator and really didnt want to take that $100 gamble since nothing else seemed to work. I was pointed to the $5 build it yourself link shown below and I've been going for about 3-4 weeks now with now P0420 code

http://www.toyota-4runner.org/3rd-gen-t4rs/175242-how-make-your-own-rear-o2-simulator-$5.html

Good luck man. if you saved your old sensors I'd use it as a test run before cutting up a good sensor. I did not save mine and was pretty nervous about cutting up a perfectly good week old sensor