Fuel PSI issues

[supernac]

My 93 explorer xlt 4x4 has been getting hard to start lately. I decided to check the fuel presser, I'm getting only 25psi at idle, and once the engine stops the pressure drops to zero. Is this normal for an explorer? It seems low to me.

 

[boggs1227]

not sure of the correct psi rateing but it think it's something like 40-50 psi to be normal. pulled the plugs and are they wet from gas ? any gas in the fuel pressure regulator vac line ? factory fuel pump ? ...could be that the check valve in the pump is has failed and letting pressure bleed back into the tank so your fuel pump could be needing to be replaced .also if you had gas on the plugs depending on what side you pulled a particular spark plug ...could be that a injector is stuck open and is bleeding off fuel line pressure that way .......

 

[ricco750]

My 93 explorer xlt 4x4 has been getting hard to start lately. I decided to check the fuel presser, I'm getting only 25psi at idle, and once the engine stops the pressure drops to zero. Is this normal for an explorer? It seems low to me.

Hi, neighbor. Per the Haynes manual, you should be getting at idle 30-35 PSI with the vacuum hose connected to the Fuel Pressure Regulator...with the hose disconnected you should be getting 35-45 PSI. Key on, engine off should yield 35-45 PSI.

The pressure should not drop to zero when you shut the engine down, it should hold steady. My hunch is that your fuel pump is about to go south in a very inconvenient way.

 

[supernac]

I noticed the pump is making a whining noise as well, looks like I will be swapping it out soon. I'm going to go with the airtex kit from rock auto, anybody have any issues with this kit? Wont be able to do it until the following weekend, hope it lasts that long!