Smidgerine

Thanks to the forum I finally got my 2K SE MT (federal, I'm pretty sure, but will check) running back for a month after the MAF IACV fiasco.

I got a tank of gas a few days ago that was ethanol-free super unleaded. I've always put super unleaded in it, but obviously in the last few years, the gas has had ethanol in it. About a day ago, my SES light came on. I took it to auto-zone and it is throwing the P0138 code.

From researching here it doesn't look like driving it is going to harm it and in fact it seems to be driving better than ever.

So, the code relates to the bank 1 sensor 2 O2 sensor and I'm betting the sensor is probably just bad, but could the fuel have anything to do with it? I hate to go spend another 160 on the sensor and then labor to install it if it should be OK. Any suggestions? Thanks!

Chris Gregg

iTrader: (59)

Secondary sensors only verify if the cats are functioning. They do not adjust fuel trim as long as the primaries are working properly. Only issue would be if your city/state requires emission testing.

ffcbairn

Interesting. I started getting P0430 about 5 months ago. Started in Vegas where the best you can get is 91oct. 10% eth. When I drove to Virginia I filled up with ethanol free along the way and that seemed to clear the code out. In Virginia I only use ethanol free and though the code progressively came back more and more until now it is on all the time. I just got new front precat yesterday, about to install on Friday. Generally I think ethanol free is definitely the way to go, I was getting 26/30.5mpg, however I do think that quality of gas can play a part too, I noticed that different gas stations would send the P0430 on more or less when it was still intermittent. I finally settled on a gas station with 0% 93oct. and it is great, gives me the above mileage with the code. My experience has been 100% positive over 10% for sure. The improved mileage somewhat writes off the higher cost. It is better for your motor too.

I would definitely try a different gas station if there is another option with ethanol free. Could be the one you bought has old or low quality gas.