A nurse returned to his car to find his catalytic converter had been stolen during a shift.
Joby Peter, 41, is one of four staff nurses at Royal Stoke Hospital, thought to have been targeted for the valuable part.
He said it was "unbelievable" and "frustrating" thieves should target medical staff during a time of crisis.
After being quoted up to £800 for a replacement, a local manufacturer offered to do the job for free.
Mr Peter noticed there was a problem with his car when it began making a "big noise" as he left work.
He said: "It was unbelievable, frustrating, something happening like this when we are living in this crisis.
"I was going to work in taxis, so when I had this, it's amazing they are doing it."
Klarius Products Ltd, a manufacturer of converters, opened up especially to fit the new part, he said.
Wayne Johnson, 46, operations director of the Staffordshire company, said he would provide replacements for the other nurses.
"We reached out and said 'we've got the facility to do it, we'll mend it'," Mr Johnson said, adding it was "really good to give something back".
He said in total, four Royal Stoke nurses with a Honda Jazz had lost the part.
"The [catalytic converter] on those cars are very high value at the moment, it's a common theft," he said.
He praised worker Dan Lucas who came in on his own time to do the fitting during a company shutdown.
Staffordshire Police has been contacted for comment.
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