MONTREAL -- Some drivers on the West Island are dealing with mechanical issues after they filled up their vehicles at an Ultramar in Roxboro.

It appears the gas at the Ultramar at 10422 Gouin Blvd. W at Rue du Centre Commercial was contaminated with water.

According to Ultramar, there is a crack in one of the underground reservoirs at the service station, an issue they became aware of last week when customers began complaining about their cars running poorly after they filled up.

The owners of the service station say they stopped selling regular gasoline immediately, and are currently only selling supreme gas.

Many cars were already affected before they shut off the pumps.

"Thursday morning, I came here about 6:30 a.m. I purchased some gasoline, regular gas, from the Romanelli brothers over here, and within two kilometres, my car started to act funny," a customer, who gave his name as George, said. "Knowing a little bit about mechanics, I knew that something was wrong with the fuel, so I pulled over, got the car parked in Canadian Tire. The following morning I came back, saw the gentleman here, told him the story. They went and towed my car here, got everything fixed."

Ultramar said it would take full responsibility for this issue.

Any driver who needs repairs as a result of the problem can either bring their vehicle to the Ultramar and have them fix it or bring it to their dealership or mechanic, and Ultramar will reimburse the cost. Reimbursement will require filing a claim through the Ultramar customer service website.

A spokesperson with Ultramar confirmed to CTV News Montreal the company will fix the problem in the next few days and expects to be operating normally on Friday.