GP out of hours care has been described as "diabolical" by the patient watchdog.
The community health council has said that care in Cardiff and the Vale of Glamorgan should be overhauled.
People are currently waiting too long to be assessed over the phone, meaning that many are turning up at A&E "inappropriately".
Stephen Allen, chief officer of the community health council told the BBC that even the basics are not happening.
"We have raised it with the health board on numerous occasions and unfortunately they are consistently missing those all important targets for the last eighteen months."
Cardiff and Vale University Health Board (UHB) telephone triage targets say all urgent cases should be assessed within 30 minutes and all routine calls within two hours.
However, in October 2013 one routine call took more than 16 hours to assess. There were also examples of urgent calls taking five hours to assess in October 2013 and February 2014.
Sue Morgan, head of operations and delivery for Cardiff and Vale UHB's primary, community and intermediate care clinical board said a service review is underway.
She said: "The GP out-of-hours service like many frontline unscheduled care services is constantly working to meet the growing demand.
"We would apologise to anyone who is unhappy with the service or care that they have experienced but would also remind people to use the appropriate support for their needs; to contact 999 in emergency situations and to make use of their local pharmacy, GP or NHS Direct if unsure which service is best placed to help them."