An ExxonMobil facility in Louisiana has been partially shut down this week while the company investigated what was causing complaints of gummed-up intake valves from area customers who fueled up with Exxon gasoline. A new report says that some 5 million gallons of the bad gas, enough to fill up hundreds of thousands of cars, was shipped out to gas stations.

Louisiana’s commissioner of agriculture and forestry tells The Advocate that two batches of the problem fuel, totaling 120,000 barrels of gasoline, were sent out in mid-March from the ExxonMobil facility in Baton Rouge.

On Wednesday, the company shut down the gasoline loading racks at that terminal to investigate a “potential issue” with fuel that had been sold nearby. There had been increased complaints about gummed-up engines in recent weeks.

One service station employee told The Advocate that he’d recently had about 40 to 50 people come in with gripes about their vehicles not starting right in the morning. The commissioner says his office has received 24 such complaints from people in the Baton Rouge area.

“What we think is something got in the fuel that shouldn’t have gotten in,” said the commissioner, whose department is now testing gasoline for possible culprits. “We need to know exactly what compound we are dealing with.”

Exxon believes that subsequent shipments of non-bad gasoline in the weeks since the problem fuel went out, so the bad stuff should be gone by now. The Baton Rouge terminal supplies fuel not just to ExxonMobil-branded stations but to other service stations that buy fuel from third-party suppliers. That terminal alone provides about 50% of the gasoline sold in the Baton Rouge area.

“We are taking this matter seriously and are investigating the issue to determine the cause,” ExxonMobil said in a statement. “We want customers to know that the fuel currently at stations meets Louisiana’s stringent regulatory requirements and is safe for use in vehicles.”

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