Date registered: Mar 2005
Vehicle: '01-E320 & 02-ST2
Location: John 15:18-19
Mentioned: 0 Post(s)
Quoted: 35 Post(s)
Anywhere from $50 to many thousands of dollars.
It could be as simple as a vacuum leak or something far more complex, even a partially clogged cat caused by a bad fuel injector and/or a bad MAS, even a bad throttle body. There are lots of potential causes and no one on an internet forum can diagnose it based on a summary of a symptom. Absent a diagnosis no one can tell you how much it will cost.
If you are not a DIYer, you'll simply have to find a good shop (whether indie or dealer, it needs to be one that knows these cars) and trust them to work up a proper diagnosis, not just run codes and replace parts hoping that will fix it.
If you are a DIYer, scroll down the forum page and find the specific forum for your car and start searching and reading some threads. Then click user cp and add your vehicle and location to your profile (it's useful information) and post a thread with lots more detail, things like mileage, maintenance history, etc.
Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy; its inherent virtue is the equal sharing of misery. (Winston Churchill)