Changes have been made to the summer car ban in Tenby after more than 20% of residents and businesses said last year's scheme was a failure.
Tudor Square will be closed to traffic between 1100BST and 1700BST
From Saturday, most vehicles will be stopped from entering or moving within the walled area between 1100BST and 1700BST until the end of August.
It is the third year the experiment, aimed at making the streets safer and ending traffic jams, has been run.
Detailed surveys were carried out in 2003 to rate public opinion.
The scheme uses cameras to read the number plates of all vehicles entering the town and those not on the approved list are sent fines through the post.
Of the businesses that responded to the council survey, 58% said it was an overall success.
Overall, 21% of the 1,500 residents interviewed regarded it as unsuccessful and 64% successful. The remainder did not know or did not answer.
The scheme was most popular with tourists themselves, with a 96% satisfaction rating.
They were also asked for key words that summed up their opinion of the scheme.
The majority said they would like it repeated and were happy with the hours it operated.
This year, residents with their own off-road parking space will be allowed one journey a day within the restricted hours and concessions will be offered for council car parks.
Arrangements will be made to accommodate weddings and funerals and there will be some concessions for boat owners needing access to the harbour.
How businesses rated the ban
Effective - 43%
Ineffective - 9%
Safe - 38%
Inconvenient - 34%
Enjoyable - 44%
Practical - 17%
The park-and-ride bus scheme will be extended to offer a great choice of alternative transport.
Pembrokeshire council's environment director Ian Westley said: "The pedestrianisation experiment for 2004 has been improved by some very positive dialogue.
"We are all hopeful that the concessions that have been made by all parties will result in a successful scheme for the coming summer."
But some say the changes have not gone far enough.
Alistair Mackay, of the Tenby Walled Town Residents Association, said people living in the ban zone needed more access to come and go in their cars.
"We welcome the limited changes made but do not consider they solve all the problems that exist for residents without off-street parking," he said.
"Those without off-street parking should be allowed access to their properties.
How residents rated the ban
Effective - 45%
Ineffective - 7%
Safe - 47%
Inconvenient - 24%
Enjoyable - 55%
Practical - 27%
"For sure in July and August there needs to be some sort of control on traffic but we feel that can be done without affecting the lives of people living here.
"Residents cannot have couriers dropping packages at their homes, building work is difficult as they are restricted, even deliveries of milk.
"My life is effectively controlled by the council as I cannot drop off or pick up anything from my house by car between 11 and five."
Further surveys will be carried out over the next months to evaluate this year's scheme and see if further changes can be made.