The protester made the alteration overnight to highlight the crumbling state of the street.
Residents say there are several 3ft by 2ft, six-inch-deep craters, as well as other smaller potholes, which are regularly damaging cars.
They want them repaired before someone is seriously hurt on the popular shortcut to two schools.
One resident said: “The new road sign made me smile but there’s a serious need for action.”
Homeowners on the half-mile-long street in Chelmsford, Essex, claim the potholes have been there for at least a year.
One said: “It’s a real problem.
“I moved here and had no idea about the awful noise of cars continuously hitting the pothole outside my house, day and night.”
Taxi driver Juber Nayeem, 24, backed the phantom signwriter’s work, adding: “Now maybe the council will be forced to fix the road.”
Chelmsford City Council leader, Lib Dem Stephen Robinson, said: “It’s a shame it takes a gimmick like this to highlight an important issue like road defects that clearly need fixing.”
Essex Highways, which is responsible for road repairs, says Patching Hall Lane is scheduled to be resurfaced in September.
A spokesperson added: “We do ask members of the public not to amend signage as it can mislead residents and cause confusion.”
- DRIVERS have forked out a total of £10billion on unexpected repairs in the past 12 months — with some dipping into their savings, putting off work on their house or cancelling a holiday to pay the bill