A town councillor has been threatened with legal action if she fails to remove a mural painted on the side of her house targeting speeders.
Kaye Corfe, from Bideford, asked an artist to complete the work because she says her road has become a "rat run".
Torridge District Council said it was a "distraction" for motorists and has given Ms Corfe 28 days to remove it.
Ms Corfe said the community had "taken it to their heart" and she was waiting for an update from highways officials.
The street-style artwork shows the VW Beetle movie character Herbie and the words "Kill your speed".
Ms Corfe received a letter from the council saying it had received an "allegation of a breach of planning regulations".
It went on to say the mural was deemed to be a "miscellaneous advertisement" which could be "harmful to the visual amenity and a distraction for drivers using the highway".
Ms Corfe said she had been informed by Devon County Council highways staff the car image itself could stay if the wording was removed and she was awaiting an update from them about the phrase.
She added that a petition had been started locally to keep to keep the entire mural.
She said: "We want to keep the whole thing, and the community, who have taken it to their heart, are getting very cross."
The council said prosecution action could be taken without further warning if the mural is not removed.
Councillor Pete Watson, from the district council, said while he "may have some sympathy with the sentiment and message behind the mural", the authority had to treat it at face value
"Clearly there is a potential for motorists to be distracted by such a large and colourful installation at this junction," he added.