(Bloomberg) -- Boeing Co. said it will remove its Starliner spacecraft from a rocket for a deeper examination of the craft’s propulsion system valves after it scrubbed a planned launch last week.

Four of the 13 valves in the Starliner’s propulsion system remain closed and will undergo a “deeper-level troubleshooting” at Boeing’s Commercial Crew and Cargo Processing Facility, the company said Friday in a statement. Boeing, NASA and the United Launch Alliance plan to determine a new launch date after the issue is resolved, it said.

The setback is yet another blow to Boeing’s efforts to convince NASA its craft can safely and reliably ferry crews to the International Space Station. The move could result in a lengthy delay for the Starliner’s next test flight given the busy schedule for United Launch Alliance, which makes the Atlas V, and a shortage of available docking ports at the space station.

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“Mission success in human spaceflight depends on thousands of factors coming together at the right time,” said John Vollmer, Starliner vice president and program manager. “We’ll continue to work the issue from the Starliner factory and have decided to stand down for this launch window to make way for other national priority missions.”

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