There was a thread about this in the general section, what ya do is get 3 bottles
1) Put a bottle in your empty gas tank, fill with ten gallons of gas, drive around untill you burn most of your gas (dont forget to save some for the trip home
)
2) Put a bottle in your crankcase, run car for about 20-40 minutes, clouds and clouds of black smoke should come out (its cleaning) You can stop when all the black smoke is gone
3) Pour about 1/3 of a bottle in a cup and take your brake booster hose and suck it up. do it slowly as your car will want to die, repeat this 2 more times.
4) You will probably have to change your spark plugs, your 2 O2 sensors, Oil filter and getting a oil change is reccamended.
Spark plugs can cost about 5$ each depending on type and O2 sensors will probably cost about 20$ each
What is does:
Cleans the carbon out of your engine, cleans your fuel injectors, and im not sure what it cleans sending it throught your brake booster.
Its amazing what you can lean on the internet.