Do you think your auto mechanic is honest, or is he ripping you off for hundreds of dollars in unnecessary repairs?  New Jersey officials are warning drivers to be extra careful when it comes to getting their cars fixed.

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A recent investigation by the New Jersey Division of Consumer Affairs found more than 18 percent of targeted auto repair shops suggested work that simply wasn't needed.

"You really need to do your due diligence both in picking an auto repair shop, but in also - once you're there - really making sure that you're getting notice, that they're explaining what's needed to you. There are auto repair shops out there in this state that may seek to take advantage of you," said Eric Kanefsky, the division's director.

In 2013, the Division of Consumer Affairs received more than 300 hundred auto repair complaints.

What should consumers do if they suspect something isn't quite right?

Kanefsy recommends getting a second opinion from another mechanic.  He also said consumers can call the Division of Consumer Affairs to find out if the auto repair shop they want to use has ever had any complaints against it. "That's a good test that they're legitimate."

Consumers who think they have been cheated or scammed by an auto repair business can file a complaint with the Division of Consumer Affairs by visiting its website, or by calling 1-800-242-5846.