Maybe a pluged Line or bad injectors??
Did you check or replace the fuel filter ever? Also, check to see if your getting the right fuel pressure through the fuel pressure regulator. It's a tiny valve on the right side of the fuel rail with a vacuum line coming from it. It tell's the ECU that your getting the correct fuel pressure to idle the engine.
take the line off the fuel rail and have someone turn the key off use a can or something to catch the gas and if you get fuel ur regulator or any injectors are clogged. if you dont get fuel take the filter of and do the same thing under the car at the fuel filter.. if you get fuel change the filter.. if not pull al the lines apart from the tank to the filter to the fuel rail and blow air from the FRONT TO THE REAR of each line.. as you blow the lines out reconnect them from the back forward and repeat the steps above.. and when you get fuel somewhere then you found the problem... hope this helps
wow totally wrong on the fuel pressure regulator, the fuel pressure reg uses engine vacuum to ADJUST the fuel pressure at the injectors. at idle the engine has aprox 18-21 inches of vacuum and the vacuum opens the regulator to relieve some of the fuel pressure, generally around 10psi is relieved so at an idle u have 30-35 psi. as you open the throttle the engine vacuum decreases, as the vacuum decreases the valve begins to close and increase the pressure at the injectors. at WOT (wide open throttle) there is no vacuum so fuel pressure should be 40-45 psi same as when u turn the key on before u start the car.
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