I need to get this sucker fixed, my SES light comes on from time to time. When the light is not on if I use an engine scanner the code still appears. I do have some O2 simms but when I have them in to delete this I get poor mileage. When the light comes on I get poor mileage as well. When the light is off but the code still reads on a scanner then my mileage seems normal. From what i've read it's a code saying i'm running too rich or that there could be water or a lose connection in the wire. How can I go about fixing this little code so I can pass emissions this month.

 

Throw the O2 sims away and get a delete tune. Done!

 

I don't use the simms right now, did you do a tune to get rid of yours or what?

 

Simms are in, SES light is back on and not going away. I can't remember but which sensor is Bank 1 Sensor 2?

 

anyone

 

bump... OP did you ever find a fix?
I put in an o2 sim to rid myself of the p0420 code, and now I'm getting p0138.
Any help?

 

wow almost a year later nice bump! lol I can't say I ever really fixed it but it does turn on and off from month to month. I wonder if maybe it's my 02 extensions I put in, maybe they are a worse quality of wire and that is throwing the voltage off.

 

Does it turn off on it's own or do you have to clear it each time?

 

It turns on and off on its own.