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State Gas Quality

Any chance that there’s enough difference in gas quality from state to state to effect error codes? I’ve got error lights on in my car, and the codes, according to the shop, say I need a new catalytic converter. I live on the border of Oregon and Washinton. If I drive long enough with Washington gas in my car, (usually just over one tank) the idiot lights go out, but if I get gas in Oregon, they come back on within a few miles. I’ve looked on the interweb, and can’t find anything that tells me what the difference in gas quality laws are, much less how they might affect my emissions.

Here in Colorado, we have “summer” and “winter” gas blends. Cars run different at our altitude and we have had a long history of winter temperature inversions making smog worse. Our fuels are blended with alcohol or other additives to help reduce emissions. I’ve never had a CEL error code from different fuel blends in 35 years of driving here. Your car may have cat, O2 sensor, or other issues that need to be addressed. Take it to an independent shop specializing in your make and have them run diagnostic tests.

Year, make, model, mileage is what controls CEL’s, not which state you buy your gas in…The CAT code is actually generated by the rear oxygen sensor which is MUCH cheaper to replace than the CAT…

state gas quality
The difference between gasolines varies more from one region to another having more to do with climate then the politics of a state. Can you imagine one day with advance technology that your car would stop running when you crossed the state line without paying your excise tax or even if the owner was delinquent in paying his State income tax...sure. But that has nothing to do with gasoline.