CHICAGO (CBS) — Customers of BP could be in line for a few bucks, if they unknowingly bought tainted gasoline last summer.

WBBM Newsradio’s Bernie Tafoya reports thousands of motorists already had received reimbursement checks from BP for bad gas bought between mid-August and early September last year at gas stations in Illinois, Indiana, Wisconsin, and Ohio.

Other motorists were waiting out a class-action lawsuit, which recently was settled for $7 million.

As part of the settlement, BP will cut checks for up to $50 for people who can prove – with a receipt – that they bought any of the bad gas. BP also will pay out up to $1,500 for repairs to fix engine problems caused by the tainted fuel.

Nearly 600 gas stations in the Midwest received the tainted gasoline, which had been contaminated with high levels of a polymer reside that is difficult to burn in car engines.

In total, approximately 4.7 million gallons of bad gasoline were sold at stations in Indiana, Illinois, Wisconsin, and Ohio.

More than 7,900 car owners filed claims for repairs to their vehicles, many of which ended up stalling or having hard-starting issues caused by the bad gas.

Many vehicles ended up crippled, and in need of significant repairs.

For details on the settlement, click here.