Q: Vehicle hard to start, but runs well once started.

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Vehicle hard to start, but once it is started it runs well. It also idles well with no misfires.

Hi there, The problem you are having is most likely due to the fuel pressure not holding it’s static pressure to the injectors. The fuel system needs to hold fuel pressure to the injectors in order for the injector to spray fuel into the engine as soon as you start cranking your engine. If the fuel pressure drops after you shut off your vehicle then the next time you crank your engine the injector will open, but there is no fuel there to inject into the engine and it will take about five seconds of cranking to get the fuel pressure built up enough to start injecting fuel to start the engine. YourMechanic would perform an inspection, they would test the fuel pressure and isolate the problem as being either the fuel pump check valve, regulator or a leaking injector. If it is an injector then you would have a rough running engine until the excess fuel gets burned off. Once tested and the failed component is isolated, then the repair can be done.

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