Plans to turn the narrowest part of St John's Road one-way have been delayed until mid-autumn.
The changes are being postponed until the autumn half-term to allow officials to gather more information about air quality and traffic data.
Conducting research before the trial in September and October will mean the outcomes can be evaluated more efficiently to see whether it is a good decision to change road plans.
The Minister for Infrastructure, Deputy Tom Binet, says the small stretch of St John's Road has been a concern for a long time.
"It’s particularly narrow for two-way traffic, and the pavements are also exceptionally slender.
"We want to see if the situation can be improved for St John’s Road residents and those who walk in the area."
In April, the Infrastructure Minister, Deputy Tom Binet, the Constable of St Helier, Simon Crowcroft, and the Parish Roads Committee agreed that a one-way system (northbound) should be trialled on the road between the junctions with Parade Road and Cheapside.
Two months later, it was announced a three-month pilot would be enforced by late summer, which gathered 25 responses by email and a petition that 720 islanders signed.
"We’ve listened to the initial feedback about the scheme - both supportive comments and people’s concerns - and we want to be clear about any benefits or issues at the end of the trial.
"This short delay will enable us to get some more baseline data for comparison."