Is the car showing a CEL? Any codes showing?

4.08 VLSD, NICO 8-way ECU, full exhaust with custom headers,
Tokico Blues with Eibach springs, Stillen FSTB, 20mm RSB, 255 rear rubber.
Some people never observe anything. Life just happens to them.
They get by on little more than a kind of dumb persistence, and they resist with
anger and resentment anything that might lift them out of that false serenity.
-Mother Superior Taraza

Have you replaced your plugs. There are a few other sensors that have a life span. Although the owners manual does not specify things like the O2 sensors actually have a life span, and may require replacement after a certain amount of time. Things like proper tire inflation, quality of fuel used, amount of weight in the trunk, condition of your air filter, and loads applied to the engine will all have a negative effect on fuel economy. Any recent service info would be helpful in assisting you in the right direction.
Oh and whats your oil level like and what type of fuel have you been using?

Modified by SteveTheTech at 1:43 PM 8/31/2008

Modified by SteveTheTech at 1:44 PM 8/31/2008

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