When a corn plant grew in the muck along the curb on 24th Street in the South Side, Dan Vito decided it was time to dial 311, the number touted two years ago as Mayor Luke Ravenstahl's Response Line.

His calls prompted a public works crew to come out and, according to city records, they "cleaned what the [street sweeping] machine could clean."

Mr. Vito, though, saw no change, and his ultimate goal -- getting regular street cleaning for the block on which his Fireborn Studios sits -- is unfulfilled. "I've given up," he said.

His result epitomizes the conundrum created by the 311 line, Mr. Ravenstahl's attempt to create an easy way for residents to report problems and for the city to track them. It has created expectations and partially fulfilled them, often prompting quick action but rarely driving big changes. The system is set to get a technology boost today with the unveiling by the mayor of laptop computers that building inspectors will use to field complaints and promptly turn them into violation notices.

Mr. Ravenstahl said he's happy with the 311 line.

"Overall, it works, specifically on the more manageable, smaller issues -- potholes, street lights, trees," he said. "We maybe have to do a better job of managing expectations on what the line does."

The 311 line replaced a service center that had its plug pulled in 2004. Since its inception in October 2006, the 311 center has gotten 81,613 requests for help, and counts 72,749 of them as completed.

Michael Stevens, a Squirrel Hill resident and Carnegie Mellon University software engineer, said he used the 311 system to report a drainage problem on Forbes Avenue that was creating a sheet of ice at a busy intersection. "I called and the next day they were out there digging up stuff and fixing it," he said.

By contrast, a February report of a collapsed catch basin at the corner Maryland Avenue and Holden Street in Shadyside, and a subsequent May call on the same problem, haven't brought improvement. On Monday, grass and weeds grew from the dirt trapped by the wobbly basin lid.

The 311 staff passed the problem to the Pittsburgh Water and Sewer Authority, which reported yesterday that it is slated for a fix within a month.

"Sometimes, it just takes time," said Wendy Urbanic, the 311 coordinator who oversees three full-time and four part-time staff members. "We're not out in the field to check that these things are done."

The city has begun sending regular "not-yet-done" reports to 27 of its public works, building inspection and animal control managers, needling them to resolve complaints that have lingered beyond deadlines.

"It sets up some interesting competitions," said Chuck Half, the administration's data king. "The different services want to say, 'We didn't get any [not-yet-dones] this week.'"

Some problems go beyond the city's capabilities.

In late 2006, Fred Smith of Lincoln Place wrote to the mayor, reporting runoff from his neighbor's yard. What followed was an odyssey of phone calls with building inspectors, planners and water authority supervisors -- but no results.

"I keep calling different people," said Mr. Smith. Meanwhile, his retaining walls lean, his basement walls bleed and his yard erodes.

Acting Chief of Building Inspection Daniel Cipriani said the city doesn't have enough staff to get involved in runoff complaints from one property to another, though its building code bars runoff that becomes a health hazard or nuisance.

Community groups have used the 311 line to try to make their voices heard. "At first, we did," said Maryellen Hayden, head organizer for the Allegheny County chapter of the Association of Community Organizations for Reform Now.

Recent calls to 311 asking the city to clear two weed-strewn Homewood lots, though, produced no quick result, she said. A small demonstration brought clean-up crews out.

"You have to raise hell, and call 311, and call 311 again, and call 311 again," she said, "and then do [a protest] action."