Do you use them?
How often?
Which ones?
What has improved?

ex. injector cleaners mpg enhancers octane boosters

 

STP Octane Booster - Cleans Injectors & Boosts Octane, use a bottle about every 3 months.

 

Octane booster. Just put it in so ill tell you if it helps when i fill up

 

A little vegetable oil with some tiger claw tea.

 

I do, but i only buy top quality ones. I've heard some stories about the cheaper ones taking the fuel pump to hell. Usually i'll just run some lucas thru my gas about once every six months.

 

In the winter and every once in a while in the summer I drop some Iso (ONLY ISO, NO METH) dry gas in the tank. As you may know, some stations do get water in their tanks that end up in our tanks!

Zack

 

i just use a fuel injector cleaner and an octane booster once about every 6 months or so...but nothing other then that

 

Sea Foam and Yamaha Ring Free ( Techron )

 

i typically use Marvel Mystery oil once ever three months or so...

 

Gives me gas......[:'(]

There are few "additives" on the market that I ever found useful, that regular sevicing didn't provide. BG Products makes some of the best stuff I've seen, all the way around.

I'd have to go with the Marvel Mystery Oil as well. Had a car with 155,00 that it was used all it's life. (Step-dad's car) Ynaked the engine at 155,oo due to nylon from the timing gears in the oil pump pick up screen, and decided to freshen the motor up. It looked like a motor with 50K on it, NOT 155K.....

Regular oil changes every 3-4K and never beaten. (Crown Vic 302, 1985)