The final part of works around Eastway in Fulwood is continuing to cause traffic problems.
A line of traffic cones on the roundabout close to the Evening Post is continuing to create traffic problems at busy times.
It is down to work to relocate a valve on the water main.
County Coun Michael Welsh, who represents Preston North East, said: “The ghosts of the Eastway improvement scheme continue to haunt us.
“Residents have pointed out that there is still a line of traffic cones on the roundabout as one approaches the Evening Post junction and this is causing problems at busy times as traffic turning right to Asda is obstructing vehicles continuing along Eastway.
“The explanation is that a valve on the water main was uncovered during the works; it did not feature in United Utilities records – these things happen. Arrangements are being made to relocate the valve but it is proving a tortuous process.” Work started last June to add two extra lanes.