Thousands of vehicle owners will receive vouchers for free rechecks from the NZ Transport Agency (NZTA), after it revoked The WOF Man owner Donald Stewart McLean's vehicle inspecting authority yesterday afternoon, and that of his business.
It cited his failure to properly inspect brakes, exhaust systems and corrosion repairs.
The NZTA said it had held concerns about Mr McLean's warrant of fitness (Wof) inspections for about seven years.
Mr McLean rejected the NZTA's claims and said he was proud of the standard of his inspections. He vowed to fight the decision in court.
In a statement yesterday afternoon, the NZTA said Mr McLean had a history of conducting poor-quality Wof inspections, resulting in upheld customer complaints.
He had also allowed his personal issuing authority to be used in inspections he did not perform, the statement said.
In all, 3515 vehicle owners have a current Wof issued by The WOF Man, and the NZTA will contact them to offer free vouchers for re-checks.
Meredith Connell managing partner Steve Haszard, who is now leading the NZTA's regulatory function, said because of the way in which Mr McLean was failing to properly inspect cars, it was unclear which of the previous cars he had checked might have issues.
''It may well be that none of them do, but we don't know that.''
Mr Haszard said the NZTA had long held concerns about the quality of Mr McLean's work, dating back to about 2012.
''The WOF Man has a long history with NZTA and not providing a high level of service.
''For many years now NZTA has been attempting to get him up to the required level, and sadly he has not achieved that.''
Under the old regulatory regime, it had an ''education-based ethos'' where it would try to educate inspectors to get them back to the level required, Mr Haszard said.
But under the new rules the agency had adopted a harder line.
The legislation allowed Mr McLean to appeal to the District Court.
Mr McLean was adamant yesterday he would fight the decision, saying the NZTA was ''absolutely incorrect'' in its assertions.
''I am proud of the standard of my warrant of fitness inspections.
''It's come as a complete and utter shock.''
Mr McLean alleged the upheld complaints against him and his business ''cannot be substantiated''.
Responding to the accusation he had allowed his issuing authority to be used in inspections he did not perform, he said that was due to an administrative error by a staff member while he was in hospital.
