Originally Posted by fordman18

i was thinkingg i needed one. but what do they even do to the engine?

sorrry for the nubby question

Originally Posted by rockercar

Here is a good reference on how to perform a basic engine tune up-changing a air filter. In most cases, It may cost you a thousands of bucks to tune up your engine but if you have some knowledge in tuning up you may start to do it to lessen your expenses.