In the mornings as it gets colder my car is taking longer and longer to turn over it takes like 15 seconds in this weather but when it’s been started it starts quickly after it’s been started even if only for a few seconds it still starts a lot quicker it fires right up when the engine is warmed all the way up but if I go a place and leave it for a little while it will crank for a exponentially longer time depending on how long it has been sitting till it is cooled all the way down then it’s back to like 15 seconds. Any suggestions on what’s wrong I’m thinking maybe a sensor btw the engine was rebuilt recently so I don’t think it’s compression or anything mechanical in the head or block
My car has a manual transmission.
You may want to check to be sure the fuel pressure regulator is working properly. The fuel pressure regulator is a device which controls the pressure of fuel supplied to the fuel injectors on an engine. This works by bleeding off a portion of the fuel flow to the injectors from the fuel pump to control the fuel pressure. Fuel is pumped from the fuel tank to the fuel rail by the fuel pump. The fuel pressure regulator is normally mounted after the fuel rail to ensure that the fuel rail has priority in fuel flow. The valve in the regulator controls the amount of fuel that is bled from the fuel rail by opening an outlet port to allow fuel to flow back into the fuel tank. All injectors need a pressure difference between the inlet and the outlet of the injector to spray fuel into the combustion chamber. This is called the base pressure. If this is not happening correctly, you will experience intermittent fluctuations in starting and maintaining the engine running as you have described. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.
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