In my continuing effort to find the least extensive repair to clear the Engine light as the result of secondary air Injection problem, a mechanic has suggested to use Seafoam cleaning. He is convinced my engine ports have the carbon built-ups, and Seafoam can fix the problem. I have a 1996 S500 Coupe with about 93,000 mi. all other parts and lines are checked and no problem. Has that worked for anyone? Please advise. thanks.