Fuel pressure?

[BuckHunter]

I have a 2002 ranger 4x4 3.0 when I go to start it during a cold start it stumbles just very so slightly. But if I turn the key on and off about 4 times without starting the truck it does not stumble at all. I'm getting ready to check fuel pressure at the rail. My question is besides the fuel pump what else could be causing this that I need to look at. And where is it located thanks? BTW once it starts no spitting or sputtering at idle or going down the road runs like brand new. And no check engine light.

 

[Dirtman]

Sounds like the pump itself is working fine but you have pressure bleeding off. In 2002 pressure should be 65psi and you have a return less system so there is no external pressure regulator. Either a fuel injector is leaking (it only takes a TINY leak to bleed off the pressure), there is an external leak in the fuel system (you'd smell or see gas), or the regulator/check valve in the fuel tank is bad. The last option is not an easy or a cheap fix. The fuel pump is in the fuel tank, bed has to come off the truck to replace (it's all one unit you cannot just replace the regulator or check valve) and they run about $300.

 

[BuckHunter]

Ok, thanks I'm not smelling or seeing any gas. So probably looking at a new fuel pump. If a injector is leaking will I smell gas?

 

[Dirtman]

Ok, thanks I'm not smelling or seeing any gas. So probably looking at a new fuel pump. If a injector is leaking will I smell gas?

No. To test for a leaking injector let the truck sit overnight. In the morning before you try to start it hold the gas pedal to the floor, this shuts off the fuel injectors so the engine should not start. Now turn the key and try to start it, if it tries to start or even just stubles for a second you know you have a leaking injector.

 

[BuckHunter]

Ok thanks Dirtman

 

[RonD]

In 1998 and up Rangers, the fuel pump assembly in the gas tank has the fuel pump, of course, but also the Fuel Pressure Regulator(FPR)

Either can cause loss of pressure with key off, without the smell of gasoline

So changing the fuel pump assembly changes both
No, you can't get FPR separately but you can get fuel pump separately

 

[BuckHunter]

So if I buy a new OEM fuel pump the regulator will be on it?

 

[Dirtman]

Yes, it comes as one big unit with the whole float assembly, pump, regulator etc.

 

[BuckHunter]

Ok, thanks I'm going to check the pressure first. Then go from there my luck it will be fuel pump.