How do you fix a fuel air ratio on a eclipse?

To fix the fuel-air ratio on a Mitsubishi Eclipse, first check for any vacuum leaks, as they can affect the mixture. Use an O2 sensor and a wideband air-fuel gauge to monitor the current ratio while making adjustments. If necessary, recalibrate the fuel injectors or adjust the fuel pressure regulator. Additionally, consider tuning the engine's ECU using a tuning software or a performance chip to achieve the desired air-fuel mix.