Yesterday, I came out and my 2002 Ranger (4.0 SOHC V6) wouldn't start. Cranked fine but would not fire up. I confirmed there was spark so assumed fuel issues. I had planned to replace the fuel filter, anyway, so went ahead and did that. Now, it starts fine -- but it won't continue running. Right after it finishes the "startup" cycle, it falters and then dies -- like it is running out of fuel. I definitely hear the whine of the fuel pump like usual so it is running.

Is this probably a bad fuel pump? Since replacing the filter at least let it get enough fuel to start, maybe the filter had been going bad for a while and the increased resistance killed the fuel pump? Other recommendations?

 

In a 2002 there is a fuel pump and a Fuel pressure regulator(FPR) inside the gas tank
You fuel filter should have had 3 hoses connected
1 goes to the engine
2 go back to the gas tank
One is for the pump and the other for the FPR

When pump is on fuel pressure should build up to 55psi before FPR is pushed open and releases fuel back into the gas tank
So system pressure is maintain at the injectors or fuel filter at 55psi

Standard picture here of fuel pump assemble: https://i5.walmartimages.com/asr/b66...f99d6422e.jpeg

Pump is at the bottom, in the center the black/silver unit is the FPR
So replacing the assembly replace both
And yes, symptoms do read like pressure is being lost when engine is running.

Just as a heads up, 3rd party assemblies are WAY cheaper than Motorcraft assemblies, 3 or 4 to 1 cheaper, lol
But you may have to replace a 3rd party assembly within the first year, its under warranty, but still a pain to swap it out
So keep the warranty handy
Nothing wrong with 3rd party, its just a heads up

 

Thanks for the reply, RonD. I've seen some articles indicate some Rangers have both a hi-pressure fuel pump and a lo-pressure fuel pump. So, my 2002 w 4.0L SOHC only has the one in the tank?

 

I'm not sure how these two-inlet fuel filters work. If I'd mistakenly swapped the two inlet hoses during replacement of the fuel filter, could that result in this behavior where it starts but doesn't keep running? Since it originally wasn't starting at all and replacing the fuel filter fixed it so it now starts, it seems odd that it won't keep running.

 

Only pre-1989 Rangers had 2 pumps
1989 and up just had the one pump in the gas tank

I think the 2 connectors that go back to the gas tank on the filter are a different size 5/16 and 3/8s, on the gas tank they are, but not sure on the filter
But no, that shouldn't cause an issues since there are on the same side of the filter

The filter would have had to have been completely clogged up to cause a no start
As a fuel filter starts to get clogged up you would have noticed a lack of power at highway speeds getting worse over the last month or so, did you?

Its very odd for a dirty filter to cause a No Start, limited RPMs yes, but start up and idle requires very little fuel
So it's odd changing the filter allowed start up from a No Start condition, so not sure if that was the problem
Unfortunately the 2002 Rangers didn't have fuel pressure test ports on the engine, so can't test fuel pressure easily

Was the vehicle running fine in the days before the No Start?

There are two filters in these systems(actually 3 if you count injector filters, lol), the one you changed, and the one in the gas tank on the pump, its called "the sock", it lays flat on the bottom of the tank and pump sucks fuel through it, a "pre-filter", so larger debris won't foul the pump
If external filter was indeed clogged up enough to cause No Start, then the sock could be as well, and if so gas tank would need to be cleaned out

You could pull off the connector on the filter coming from the pump
Put a container down under the hose
Then use a jumper wire in the Fuel Pump Relay socket(engine bay fuse box) to turn on fuel pump full time, and TIME it, run it for 1 minute
See how much fuel is pumped out

They are usually rated at about 30 gallons per hour, so 1/2 of a gallon in a minute
If its much less then pump is failing or sock is clogged

In 2002 I think Ford used Micro relay for fuel pump, contacts seen here: http://www.gtsparkplugs.com/images/m...lay-wiring.jpg
If you connect slots 30 and 87 together with jumper wire then fuel pump should come on full time, key on or off doesn't matter so have it off

EDIT:
Just as an after thought............Take off gas cap and start engine
Extreme long shot........there is an EVAP system that creates a SLIGHT negative pressure in the gas tank so fuel vapors, that occur when gas is sloshing around when driving, do not pollute the air, these vapors are sucked in to the intake by vacuum and are burned in the engine
IF(big if) there was full vacuum applied to gas tanks EVAP system then you could create enough negative pressure(20") to cause failing pump to not be able to lift fuel up and out
Way long shot, but all you have to do is to remove the gas cap.............so why not try it, lol


You can get PDF version of your owners manual here: https://www.ranger-forums.com/genera...1-models-3747/
Nice to have when looking up fuse and relay locations, easier to use than a book

 

Here's the pertinent history

• Generally, this truck has always run great - starts right up, no performance issues. I've driven it 43k miles since purchase in 2008. I don't drive it every day, maybe average a day or two every week or so; more some weeks, maybe not at all other weeks.
• About 18 months ago, I had an experience where it would not start after driving it for a while. (Drove to the store, did some shopping, came back out and it wouldn't start.) It was trying to fire but just couldn't quite get there and it felt like not enough fuel or something. I let it sit for a while -- maybe 15 minutes or so -- and then it started right up and ran fine. Given that behavior, I assumed it was vapor lock or something similar.
• About 1 month ago, I had that same experience again. Exact same behavior and situation. After letting it sit, it started right up and ran great.
• Last Monday, I drove it and had no noticeable issues at all; ran the same as it always has -- started right up, no noticeable performance issues, nothing.
• Wednesday morning, I went to drive it and it would crank but would not fire. I tried starting it about five times, each time running the starter longer than usual trying to get it to fire up.
• I tested and confirmed it had spark so began looking at the fuel possibility. I tried squirting some Sea Foam in past the butterfly to see if it would fire up but it did not. Maybe I just didn't get the Sea Foam in enough of an amount or deep enough for it to help. But it was obvious I had spark so I still assumed a fuel issue.
• Having been planning to replace the fuel filter anyway, I decided to replace it just to eliminate that as a question.
• After replacing the filter, it started up immediately like it had previously. I shut it off after just a few seconds.
• I then cleaned things up and went to move the truck. It started right up but wouldn't continue running. I started it about five times with the same result: immediate start with a no-struggle start cycle then would die as it idled down.
• This morning, I went out and tried again. Now it still starts but it clearly is struggling, only getting a decent start cycle one time while the other several attempts didn't even get it to idle-up during the start cycle.
• I tried removing the gas cap and putting it back on. No change in behavior.

Other than the two events I described above, there have been zero indication of any significant issues and it had been running great just the last time I drove it. It isn't like I've noticed a gradual reduction in power or gradually increasing difficulty of starting. One day it was great, the next day; Nope. For such a binary change -- well, that just seems really strange.

 

First, I checked the fuel filter connections and the two hoses to the inlet side are different size connections so I couldn't have mixed them up.

Second, I went out to check it with my scan tool just to see if it was now throwing DTC codes or anything. (It hadn't thrown any at all when I originally checked, but...) This time, it started right up and kept running. I let it run for a couple minutes and it seemed fine. So I tried revving it up some and found that it stumbles at 3,000 and won't go above that. I don't remember encountering that before; pretty sure it will rev up to red line even while in park. But I'll check it out tomorrow when I have more time.

Third, if there were fuel pressure issues wouldn't that throw a P0087 DTC code?

 

First the P0087 code, no, our Rangers never had a fuel pressure sensor, computer just expects 55psi(1998 and up) and will start to throw Lean codes over time, if say the pressure was below 40psi, but it would take a few days to a week of driving for that

There is a "REV limiter" in the computer that starts to limit RPMs at around 3,000 when in Park or Neutral or if speedometer is under 5MPH, so that's normal

Could the "new" fuel filter be the problem, just saying "new" doesn't mean what it used to mean in the past, lol
New used to mean tested and working
Now it means YOU TEST IT, and we will replace it if it doesn't work

You do have symptoms of one of the fuel pump failure modes
Sometimes they just quit one day, out of the blue, but never while driving, at least I have never run across that one, so just a No Start and thats it until pump is replaced
Sometimes they will provide limited pressure, under 40psi and you will start to get Lean codes on both banks, and limited power, same as dirty fuel filter
Sometimes they will start up for that key on 2 second run time, and then not start again after engine starts up<<<<what you had

For reliability I think you will be replacing the fuel pump assembly, not sure I would trust it will start "at the store" or ???

 

@RonD Again, very much appreciate your time in helping me through this. I guess I'd forgotten about the rev limiter. Regarding the "new" fuel filter: All I know is that the engine wasn't starting at all -- not even an attempt. Then I replaced the fuel filter with this one (new from the store) and it immediately would start. Of course, it would start but not continue running, then this morning was struggling to start, and this afternoon started and stayed running. So, based upon all the symptoms, you recommend replacing the fuel pump?

BTW: I've been looking around for a fuel pressure fitting but, as you indicated, there doesn't seem to be one. From other photos, I found where it should be (and apparently is on some later years) -- sample from an Explorer 4.0 below:

Explorer 4.0 fuel rail Schrader valve

But that same location on my 4.0 doesn't have any fitting. Just has a 'T' with a couple hoses connected -- see next photo. So, not sure how exactly I'd test the fuel pressure anyway. (New experience for me.)

2002 Ranger 4.0 SOHC fuel rail end -- no fitting

 

I believe the "T" you are looking at is on the driver side front fuel rail. There should be a Passenger side fuel rail attached to the end of the hose coming off the passenger side of that "T". If you can, look at the other side of those fuel rails. The drivers side should have a fuel rail pressure damper with a vacuum line attached to it. The passenger side should have the Schrader valve you're looking for.

 

How many miles before the 48K you put on? just askin'

 

I bought it in Sept 2008 with 30k on it. I average about 5-6k per year on it and it has about 74k on it now. 'Been a great truck.

 

You win the prize! There are a couple of hoses and a wire cable I had to move out of the way but then was able to see the fitting on the rear end of the passenger-side fuel rail.

Passenger-side fuel rail, rear

 

UPDATE: This morning, it again started right up and continued running. I took it for a short, easy ride down our lane and back and there was no indication of any problem. Then I took it out on the county road and drove it normal until it warmed up and then turned around and drove it hard -- up a hill, full throttle, foot to the floor, winding out each gear (shifting at about 5,200 rpm). Not a single indication of a problem, it was exactly as it has always been. If I hadn't experienced the last few days with this issue, I'd say there was nothing wrong. I find it difficult to believe that replacing the fuel filter had any significant impact on this situation.

I greatly appreciate all the time spent sharing your thoughts. At this point, I feel to monitor this for a while. Now, that I know where the test fitting is, I'll get a tester and check the pressure. Assuming that is good, I'm going to wait and see if I have another instance of the "won't start after coming back out of the store". If that happens, I'll call it done and replace the fuel pump.

 

Yes, that's a pressure test port, good find

Just as an easy to do check, pull out the Fuel Pump Relay and check its socket and pins for corrosion, and simply pulling it out and putting it back cleans off these contacts, in case there was a build up
Do the same for fuel pump fuse