Western Refining spokesman Gary Hanson says a gasket failed, allowing water to leak into a petroleum storage tank near Gallup last week. The company has established a claims hotline at 1-877-511-1012.
The contaminated gas was also sold at 10 additional convenience stores across parts of New Mexico and Colorado.
In Arizona, it went to stores in Springerville, Show Low, Teec Nos Pos, Holbrook, Flagstaff, Pinon, St. Johns and Keams Canyon.
See the complete list of Arizona locations below.
COP 138 W. Main Springerville 85938
Shell 1790 S. White Mountain Road Show Low 85901
COP 1981 E. Deuce of Clubs Show Low 85901
Mustang Jct 64 & 160 Teec Nos Pos 86514
Maverick 1301 Navajo Blvd Holbrook 86025
Safeway 900 W. Deuce of Clubs Show Low 85901
Mobil 3960 N. Country Club Drive Flagstaff 86004
COP Intersection of BIA Rte 4 & 41 Pinon 86510
Apache County 120 County Road St. Johns 85936
Keams Canyon 403 Hwy 264 Keams Canyon 86034
So far 300 people have filed claims. 60 claims have been filed in Arizona because of the bad gas.
Warning signs include the engine missing, stuttering, or a check engine light that just won't go off. It may even quit running.
Customers who have filled up with the contaminated gas may have issues that could take up to two days to fix at a cost up to $1,000.
Western Refining is paying for repairs, provided there's documentation for the Oct. 8 gasoline purchases at the affected stores along with any repairs that have been made.
Two stores in far southwestern Colorado also received contaminated gas. The supplies since have been replaced.
In a letter on the company's website, Hanson said, "We appreciate your business and are sorry this has happened. We want to correct this situation for anyone that was impacted by our mistake. If you purchased fuel on October 8 from any of the stores listed below please call 877-511-1012 and we will assist you in your claim."