A vehicle inspector in Coromandel has been suspended after being accused of attempting to delete failed checks from the vehicle inspection database.
The Transport Agency suspended Warwick Shelley who manages - and is the inspecting organisation delegate - at both VTNZ Thames and VTNZ Whitianga.
"An NZ Transport Agency investigation has found evidence that Mr Shelley ... has been overruling his vehicle inspectors when they fail vehicles," it said in a statement.
He was also accused of failing to properly inspect critical safety systems, including brakes.
There was a "strong possibility" some vehicles may have been incorrectly given warrants (cars) or certificates (trucks) of fitness.
The agency said it was contacting 4850 vehicle owners about getting a re-inspection, which could be done at any VTNZ site for free.
VTNZ would be installing a new delegate to run both sites and oversee the rechecks.
Earlier this week, an Auckland garage was suspended for failing to carry out warrant of fitness safety checks properly. NZTA found an unauthorised staff member had been doing warrant inspections.
Last week, NZTA suspended two garages in Auckland - at Whangaparaoa and Ōtāhuhu - for wrongly issuing warrants of fitness, affecting nearly 3000 vehicles.
Just last month, an independent report found systemic failures within the organisation.
It did, however, warn that tougher enforcement from now on would mean garages, certifiers and transport operators would get caught.