Alright guys, I need some help. I am new to the forum and I do not know a whole ton about cars and trucks but I do what I can to learn on my own and repair anything that I can without having to pay someone else to do it. I have a 2004 Ranger 4.0L. When I get in the truck to start it sometimes it cycles for a while and will either turn over or I will stop and retry. Either way, its always starts after no more than two turns. This problem has been going on for a few years, but I have not had the cash to fix it and since it has always started without fail I have just left it be. However it does seem to be getting worse lately and I want to get it fixed before it won't start altogether. From other posts I have read it sounds like the fuel pump, so I have explored that. Here are the things that I have done:

New fuel filter, techron fuel system cleaner, checked the gas pump relay switch, and I just completed a pressure check on the system. I cleared the pressure by pulling the pump fuse and starting the truck. Once it died I made sure the pressure meter was set to zero and turned on the power to the truck. It went up to 20psi, then I started the engine and it went to 68psi. I turned off the truck, bled the valve and turned on the key to start the power again. This time through (since the system already had gas in it) the psi jump to about 60. After about 10 minutes the pressure had slowly dropped to about 52-54psi. Which I heard someone say is normal. Do you have any other input? The psi seem to be ok, and when I turn the key I can hear the fuel pump switch on. I am kind of at a loss. I am replacing the spark plugs and wires this next weekend hopefully as well.

 

Welcome to FTE. You've been busy on this one & have done some good diagnostic trouble shooting.
What is the engine running fuel pressure value & how does the fuel pump delivery rate over time check out??? EDIT: 1/2 pint-15 seconds is the pumping rate.
64 +/- 8psi is the fuel pressure spec.
How low does the fuel pressure drop, say 30-60 min after you turn the engine off???

 

I will have to do another pressure test to see. I know that it was running at about 68 psi when the engine was on, but I did not keep the motor running for long to see how that value held up over time. I will try to get another test done tomorrow or the next day and see what I get.

 

OK so I finally got the time between finals to work on my truck. Replaced the sparkplugs and wires this past weekend. No improvement in starting. Did another fuel pressure test. Fuel pressure while engine was running held steady at 68 psi. Turned the engine off, and the gauge read 60 psi. Checked the gauge after 30, 60, and 90 mins and got readings of 56, 48, and 40 psi. I do not know how to test the fuel pump delivery rate.

 

Sounds like its holding fuel pressure ok. You can do a volume over time test by using your fuel pressure gauge bleed off valve & hose to have the fuel pump fill a measured container over the above EDITED specified volume/time period I posted.

If it'll always start right up after first cycling the ignition from off to run 2-3 times before cranking the engine, so that the pump builds pressure to prime the system for the start, the fuel pump belongs on your suspect list, hence the fuel delivery rate over time, fuel pressure & bleed-off test suggestions.

Do you have any engine power output problems on a pull up a steep hill, or does the engine lay down when you go to WOT to pass, or make a quick change in acceleration, or top speed seems wimpy, if so, that's a sign of an under load fuel delivery, or pressure regulation problem. Delivery problems can be caused by a number of things, like a weak pump, clogged fuel filter, or clogged in tank pump sock/pre-filter, crimped fuel line, or voltage drop to the fuel pump caused by a weak battery or alternator, corrupted electrical connection in the fuel pump electrical circuit, or a computer problem that sends a pulsed/variable duty cycle signal to run the pump.

Start problems can also be caused by dirty, or worn spark plugs with excessive spark gap, or plug wires that have electrical leakage problems causing a voltage drop to the plugs. So if the fuel pressure & delivery rate under load check out ok, have a look at the spark plugs, especially if they have 60k miles or more on them, or aren't the specified double platinum, or fine wire iridium enhanced design, or are some aftermarket multi-electrode type plug, or the plug wires are not of high quality, as our waste spark ignition system puts a Double work load on the plugs & wires, so they need to be designed to hold up to that work load. OEM Motorcraft plugs & wires, or the specified Autolite plugs & wires are recommended, as our engines are kinda persnickety about plugs & wires.

More thoughts for consideration, keep us posted on your trouble shoot.