The Clean Car Discount scheme is having to alter wrong or missing emissions or safety-rating data as it goes along.

Car dealers say some customers expecting a rebate are getting hit with a fee instead, because an incomplete database is being updated even as the vehicle is sitting on the lot.

The Imported Motor Vehicle Industry Association's David Vinsen told Kate Hawkesby the Government was warned it didn't have information on all of the fleet, but proceeded anyway.

He says NZTA has been scrambling to remedy the glaring database emissions since its launch.

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