Being the offspring in a family of scientists & engineers, I cannot help but chime-in here. I must agree with "JCL" on all accounts. The best thing one can do is consistantly pump premium quality fuel into the car. This is Chevron, Texaco, Shell and other "Top Tier brands" then premium grade at these outlets. Its NOT all the same gasoline. The extra ten cents or so per gallon between these fuels & discount outlets may be considererd a substitute for the additives you may be persuaded to buy at the flashy Auto Zone store & other similar outlets. The benefits are much greater. If you do not put garbage in you do not need to clean it out. As I suggested to my wife, its like how you feel the next day after drinking Monarch or Grey Goose. If you spend more up front, you avoid the hangover.

I can't remember the last time I added aditive, I use Chevron w/ Techron or SHell V-power highest octane, never had any problem with fuel.