The Cowley Mini plant has been forced to shut down for two days from tomorrow to repair a machine used to help press the doors.
The tool, which is now being repaired, is based at the Swindon factory where the body panels are made before being transported to Oxford.
As a result, production will be suspended at the plant tomorrow and Friday before the scheduled Easter break. It will resume on Wednesday, April 7.
Employees will be asked to add the extra days to their working time account, the system which “banks” workers’ hours.
Plant spokesman Rebecca Baxter said: “We are providing updates for associates via a dedicated website and telephone lines. We are grateful for our associates’ flexibility at this time.”