what will cause a fuel pump to not build up & shut off on a 1993 ranger.when i turn it over it has 38 lb.pressure
Your thinking of the old low pressure type pumps that had a built in regulator so the pressure would lift the needle off the seat inside the carb. The system your ranger has is a high pressure system, it provides a continuous supply of fuel to the fuel rail and pumps the unused fuel back into the tank as long as the engine is running, so it never builds pressure and shuts off. When you first turn the key on you should hear the pump run briefly then turn off. That builds the fuel pressure up quickly for the initial start.
Just found your previous post, as it won't run unless you spray starter fluid in the intake and you have enough fuel pressure to start, i would check for power and trigger signal to the injectors, they have to squirt fuel for the engine to run.
thats my problem.you turn the key on & the pump comes on but never shuts off.
Then think some one has jumpered the fuel pump to ignition voltage or possibly jumpered the fuel pump relay, but the engine should still fire and run even with the pump jumpered, as I stated it is a continuous flow system. Test the injectors electrical, you could have a short or a fried driver in the ECM.
itwill run if i shoot a little gas in throttle body.it idles pretty good but when i give it gas its like its starving
Does the fuel pressure jump up when you try to accelerate the engine? There could also be an exhaust restriction. Have you checked for codes?
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