Is it necessary to “as my Dad used to say blow out the carbon” with a high speed road trip of a few miles. If you are reading this and need an excuse to go for a speedy road trip, or if your engine has a carburetor the answer is yes, But in reality it is not necessary for today’s computer controlled fuel injected engines. If there has been a problem with the system causing a carbon buildup or you use cheap gas, which will cause problems in time. Many times the check engine light is ignored, with the tough economic times we are seeing more of this, the engine seems to be running fine but it is actually causing all kinds of problems and one of these is excessive carbon build up. You are also doing damage to the atmosphere. The build can become severe enough that the engine needs to be disassembled to remove the carbon. There are several products on the market that do a decent job of removal. The only ones that work are the ones you run directly through the throttle body. Insert a vacuum hose into the can and the other end to a vacuum source or many air tubes have a hose or two in the tube itself this is most effective spot. Be sure to follow the instructions to the letter as many problems can result if improperly used IE engine damage, converter can be damaged, the O2 sensor can fail this may happen anyway. If in doubt have it done by a shop it is not that expensive also most shops know which chemical works the best in your area. Do not use water or diesel fuel as someone may tell you is OK but it will tear up an engine very quickly. I would also clean the throttle body covered here. [url”>http://www.greenflagauto.com/comments.php?id=411&catid=1&highlight=throttle+body