A blitz on taxis in Sydney's CBD has confirmed that many are in a state of poor repair.

The five-hour operation at Haymarket on Friday was launched after an ABC investigation uncovered serious safety breaches.

Officials inspected 41 taxis at an inspection site set up on the western side of Central Railway Station.

Defect notices were issued for 18 of the cabs for issues including faulty seatbelts, bald tyres and broken security cameras.

Eight infringement notices were also issued to drivers for offences including obscuring number plates.

All drivers were also breath-tested but police say none returned a positive reading.

Police from the Transport Command led the blitz, with assistance from Roads and Maritime Services (RMS) and the Taxi Council of NSW.

Officials from the Department of Immigration and Border Protection also attended to ensure no drivers were breaching visa conditions.

Taxi Council chief executive Roy Wakelin-King says the inspection shows the system is working.

"I think that the community should welcome the fact that there are these ongoing inspections," he said.

"Taxis do a lot of kilometres on the road, on average about 100,000 kilometres a year, and therefore we need to make sure we have regular inspections in place."

A qualified mechanic inspected a taxi as part of last week's ABC investigation.

Mechanic Ray Tabone said the car should not be on the road.

"As it stands, the car is not roadworthy ... we found on inspection that the two front tyres are worn on the shoulder to the point where the canvas is starting to come through," he said.

"The engine is loose... and could become a projectile in an accident.

"It's broken. You can see the engine popping up... and a whole part of the suspension is missing.

"The vehicle has had some services recently. These items should have been picked up at that service."