you might have a slow oxygen sensor have you had a chance to check them ? What is you're fuel trim you want it to be as close to 0 for long term under most load conditions. or if that car uses block learn and intigrator you want the intigrator to be as close to 128 as possible. Also does you're car seem to have a slight or loud rattle coming from the catylitic converter? Some times the catalyst will come loose causeing high exhaust back pressure which of course will cause higher than normal gas mileage as well as a lack of power and a poor idle. last but no least does you're car use a maff sensor ? do you have a k & n style air filter ? if you do the oil from the k & n can cause the maff sensor to have innacurate readings. the oil will act like an insulator cause a rich condition at low throttle postions and a lean contition at high throttle positions. if any of this stuff does not work do not hesitate to e mail me directly at
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