As I am sure alot of STS owners know, the intake manifold (and throttle body) can become quite heavily deposited with carbon over time. I have already cleaned my throttle body to resolve the infamous 'sticky throttle' issue.

My challenge now is to find someone who can successfully clean the inside of the intake manifold. I have contacted a specialist engine builder and they said they have a hot steam bath they use but fear that would not work very well on removing the carbon. They suggested trying to find an ultrasonic cleaner (which I am currently trying to do).

Has anyone else successfully cleaned their intake manifold?

Please do not offer any suggestions on using retail cans of carb cleaning spray, this only works in areas you can easily get to or where there is very light carbon (I know as I have used a full can on my manifold and it did nothing - took most of one can just cleaning the throttle body).

Thanks,

Craig