The South Australian government remains committed to adding a right-hand turn to a controversial new tram line at a major Adelaide intersection despite growing concerns over the delivery of the project.

Transport Minister Stephan Knoll said the government has commissioned new design work and engineering advice which should be available in October but remains committed to its election promise.

“But we are also committed to making sure we deliver our promises in a practical way and that’s why we’re going to wait until the engineering experts tell us the best way to deliver this project,” he told reporters on Monday.

The minister’s comments come despite further delays to the opening of the new $80 million line along North Terrace because of a signalling fault.

The previous Labor government ruled out the right-hand turn at the intersection of North Terrace and King William Street, right outside Parliament House, because of the complexity and cost with estimates it would add $37 million to the price of the extension.

Mr Knoll described the advice to the previous government as “preliminary” and said that was the reason the government had asked for more work to be done to inform its next steps.

He’s also conceded he still doesn’t know when the now completed extension will be open because of the latest fault.

“What we’ve been saying consistently is that we’re working to identify the issues that exist,” he said.

“The project team works methodically, night after night, to try to isolate and identify the problem.

“Some progress has been made but we want to make sure we come back with a fulsome answer to the South Australian public.”