Hmmm.... maybe its your driving style? Can't say for sure cause
I odn't know you or how you drive. I know several other people who
had the same problem you're facing though.
After their cars were tuned, it burnt fuel faster. Turns out that
because the cars were tuned and smoother, they rammed down harder
on their accelerators without feeling the "roughness" that was
there before the tuning. If you did that you won't get optimum
performance anyway... you'll just be wasting fuel.
What plugs are you using? Spark plugs have ratings, you need to get
the correct rating for your car.
