Auckland's new electric trains have been able to get back on schedule after initial delays on their debut run extended to nearly 20 minutes.
Auckland Transport says overcautious train staff, and passengers unfamiliar with the new door opening system lay behind much of the delay.
It said passengers need to press a button to open doors, and staff then need to disarm the doors prior to departure, and coming to grips with this has extended the time trains remain in stations.
The managing director of train operator Transdev, Terry Scott, said there were probably some nerves among staff, with large numbers of management and media watching during the morning peak.
Passenger numbers were signficantly boosted by rail enthusiasts, and people keen to try out the new trains which began before 6 o'clock on Monday morning.
The new Spanish built stock debuted on the Onehunga line, and services will extend to other lines during the next 15 months as more of the 57-unit fleet are commissioned.
Passengers spoken to by Radio New Zealand News were impressed with the first brand-new commuter trains for Auckland, in more than sixty years.
The $600 million fleet purchase is hoped to significantly boost rail patronage in the city.
The trains carried 5000 Aucklanders on short complementary excursion trips on Sunday between Britomart and Newmarket, following a VIP launch.
Auckland Transport opted to introduce the new trains gently, with the Onehunga line the shortest and least frequent in the region.
Five of the three-car units have been commissioned for service, and by mid-next year all 57 of the Spanish-built trains should have replaced diesel trains except between Papakura and Pukekohe.
The new trains can carry 40 percent more passengers than their diesel predecessors, but back-up buses are on standby on Monday morning in case there's a first-day rush.
Rail patronage is hoped to lift from 11 million trips a year to 20 million, in order to trigger Government backing, to start the downtown rail tunnel earlier than 2020.