INDIANAPOLIS (CBS) — Drivers whose vehicles have been affected by bad gas from BP are threatening to take action.

As WBBM Newsradio’s Michele Fiore reports, while the Indiana’s Attorney General’s office leads an investigation to oversee BP’s claims process, attorneys in Indianapolis and Merrillville are gathering evidence for a class action lawsuit, seeking full compensation for damages.

LISTEN: WBBM Newsradio’s Michele Fiore reports

Customers who used the bad gas, then had trouble starting their vehicles and stalling could join the suit.

BP has said it believes a 50,000-barrel batch of gasoline shipped from its Whiting fuel storage terminal Aug. 13-17 contained a higher level of a polymeric residue, which is difficult to burn in automobile engines.

While the problem is centered in Lake County, Ind., BP executives said the fuel has made its way across state lines into Illinois and Wisconsin. Motorists from southwestern Michigan have also called the oil giant.

According to a statement on the company website, the BP refinery in Whiting, Ind., has returned to normal production, but higher grades of fuel are still undergoing further tests, so won’t be sold for now. Chicago motorists pulling up to BP stations on Thursday found premium and midgrade gas unavailable.

BP spokesman Scott Dean said that more than 10,000 motorists have called or e-mailed to complain, and BP has begun paying claims.

BP said some of the tainted gasoline was sold at stations that are not BP-branded, including Thornton and Costco stations.

“BP stands by every gallon of gasoline we sell,” Dean said.

Dean said BP would pay for a replacement tank of gas and any repairs made necessary by bad gas.

Dean said customers can make complaints by one at (800) 333-3991 or 800-599-9040, can e-mail or visit

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