I replaced my fuel filter and fuel pump on my 2001 ranger. But I have to turn my key for 5 or more seconds to start. However if I let my truck sit in my driveway for a week or more without starting it, somehow the fuel lines pressure up and it starts up instantly. It also starts instantly if I just shut it off for a minute or two but if I let it sit for more than 5 minutes its hard to start and kind of struggles to get fuel to the engine for a few seconds. Weird huh? Any ideas...

could it be the fuel pressure regulator having issues?

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2003 Ford Ranger Edge 3.0 v6, Automatic Trans, 2 WD, Extended cab, Fog Lights, and Plastic Bed Liner

There was a post by RangerSaint that had a problem very much like yours so you might want to search the forum under his name. he did find the fix!

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2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.

Thanks, I read that whole forum. My problem seems to be slightly different than his tho. When I turn the ignition on my truck I don't her the fuel pump running before turning over completely to start the truck. And my truck's rail pressure recovers after about a week of sitting in my driveway without running it. Very strange. I ordered a CEL device to run a system diagnostics check.

If you released the pressure before you changed your filter the pressure release switch (passenger side kick panel wiring harness disconnect) and removed your gas cap. Then started the truck and let it run out of the fuel in the fuel lines before changing your fuel filter. Then reconnecting the Pressure release wiring harness replacing your gas cap and priming the system. In order to prime the system you turn the key to the on position, then turn it to the off position three times without starting the vehicle this sends fuel back into the system through the fuel filter as a pressurized fuel to be injected in to the cylinders for combustion. So in a long statement you might try priming the system before starting your truck.

Thanks for the reply!! I've tried priming it (turning key on & off 3 or 4 times before starting) and it doesn't send fuel. I was told that it was my ball check valve but I had the fuel pump replaced so that wasn't it. It's weird how if I don't drive it for a week the lines pressurize and it starts immediately. Could it be a faulty relay or module somewhere? I checked the fuses they were fine. I'm not an expert by any means but I just have a gut feeling it's somewhere close to the ignition system..

This could be something as simple as the gas cap not venting and there's vacuum building up in the tank and the pump can't overcome it but I would think that the pressure / vacuum sensor in the tank would see it and activate the purge valve and equalize the pressure. I say this because you said that if you let it set for a couple of days that it starts and my thinking is that the vacuum in the tank has equalized and the pump is able to draw fuel out..Just a thought maybe try and start the engine without the gas cap on when you have this issue...

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2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.

That makes a lot of sense!! I'll give it a try tonight and let you know what happens!

So you say that the fuel pump does NOT run at all with the key on and engine off. I thought that when you turned the key to on the pump should come on period, regardless of a vacuum in the tank. The computer starts the pump until the fuel pressure is up to normal. When the pressure sensor reads the correct pressure the computer stops the pump. Correct? If so could be an issue with the fuel pump sensor or the wiring/connection to it?

If a bad sensor says the pressure is ok at say 10psi you would see:
- turn engine off and immediately restart -> no problem because the pressure never fell
- turn engine off for 15 minutes the pressure drops to say 20psi. You try to start-> pump does not come on because sensor says pressure is ok; engine does not start because actually the pressure is low; you keep cranking and the pressure drops below 10psi and the sensor says to energize the pump. Once the truck is running the engine vibrations keep the sensor, which is a mechanical switch, working correctly.
- turn engine off for a week and the pressure drops below 10psi and when you go to start the engine the sensor allows the pump to start and the engine starts normally

Just a thought. Diagnose by connecting a fuel pressure gauge and prove the pump does not come on when the pressure is low.

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I would also check the fuel pump relay. Relays can fail in an intermittent fashion and are easy to replace/check.

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2009 Mazda B2300 2WD 5 Speed Manual
COMPLETED: Headache Rack, HAM Radio, Radar Detector, iPod
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FUTURE: 2 Mini Light Bars, Bed Work Lights, Aux Backup Lights, Aux Driving Lights, Fog Lights, Brake/Turn/Flasher lights on Headache Rack

Rangerman49: Removing the gas cap didn't work. Bummer. But great idea!

Milton: I just ordered an adapter so I can attach a pressure gauge. I have a digital gauge that reads from 0.1 to 200psi and 0.0 to -15.0 vacuum (reads extremely accurate to the decimals)

Unfortunately it will be a few days until the adapter gets here and I can run the inline pressure tests.
Thanks for the input guys. You both have some great ideas, I have a feeling we are narrowing in on it!