Infrastructure Minister Michelle Haywood says MOTs aren't being considered by the government.
Arbory, Castletown and Malew MHK Jason Moorhouse asked a question for written answer about progress introducing the roadworthiness tests after the new Vehicle Test Centre opened.
Dr Haywood said evidence testing improves safety is limited, and MOTs would cost the public, garages and the government.
She said mandatory testing for HGVs, taxis and buses remain in place.
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