Engine & DrivetrainEngines and Drivetrains can be a major problem for a lot of vehicles. If you are having engine or drivetrain problems, you can post your questions/concerns about the issue. Furthermore, if you are in the process of doing an engine rebuild, post your progress with pictures.
02 expedition will not start, All Fixed see post 16.
Hello all, as the weather cooled off here my wife's expedition (5.4L) began having trouble starting. The engine turns over fine but will often only start after a few tries. The problem had been intermittent until last night.
I had the battery tested and it was OK. I changed the spark plugs, air filter, and fuel filter and it started right up. I thought I was in the clear, it ran like a beast (the spark plugs had 113,000 miles on them). After I shut it off it would not start again, same symptoms as above. I have tested the fuel pressure at the fuel rail (there is none), the fuel pump fuse and relay (both work), and checked for voltage at the last connector to the fuel pump near the left rear tire (10.5v or so KOEO). I can not hear the fuel pump turn on with the KOEO at all. I checked the PATS system as well, the theft light extinguishes KOEO after about three seconds.
Sorry for the long post, I was just hoping for a second (or third) opinion before I drop the tank and spend a couple hundred bucks on a new fuel pump.
I'm pretty inexperienced with this forum thing so forgive my mistakes. My 04 Explorer Ltd did (does) the same thing but I haven't done that many things to correct it. I'm convinced that the cold is the culprit. Car will crank fine but not fire up. This works almost every time even on the coldest mornings...I turn the key to "on" and leave it for about 6 seconds then turn it all the way off. I'll repeat this and hit "start" on the 4th time. It fires right up. I feel sure the fuel pump is fine but there must be something that is allowing fuel to bleed back and lose pressure. I have no loss in power or driveability.
I know cold is a relative term, I grew up in upstate New York. We live in central California so it just isn't that cold here. I was also thinking of checking the camshaft position sensor to see if it is sending a signal back to the PCM. Thanks for the help I'll give your suggestion a try today.
Thanks for your response Wizard, I have a fuel pressure gauge and there is no fuel pressure at the rail KOEO or while cranking.
I am a bit embarrassed, but I can't find the fuel pressure regulator. Is it behind the intake manifold or something where it is out of sight?
Just FYI I did clean the MAF and will go out right now and clean the IAC valve and test it.
Thanks again for your help, I appreciate it.
Wizard Rep power +1
I tested and cleaned the IAT valve. There was a fair amount of carbon deposited on the inside and along the valve shaft. Thankfully I am a gun nut, so I had plenty of tools to clean the inside pretty well if I do say so my self.
I tested PCM input voltage (11.86v), internal resistance (10.1 ohms), and checked for shorts from the terminal to the body.
I think I have covered all the bases with this particular sensor/valve.
Thanks for your response Wizard, I have a fuel pressure gauge and there is no fuel pressure at the rail KOEO or while cranking.
I am a bit embarrassed, but I can't find the fuel pressure regulator. Is it behind the intake manifold or something where it is out of sight?
Some Ford vehicles (and I don't remember which ones) have a "returnless" fuel system. There is no "traditional" pressure regulator (which would typically be found at the opposite end of the fuel rail from the feed)
First, be certain that the inertia switch is not tripped.
Second, you could have a bad returnless fuel control module (separate from the PCM). I don't know how to specifically test for this.
__________________ Peace, it's our only chance
1998 E150 Club Wagon, 4.6L Modular, E4OD
2007 Milan. 3.0L Duratec, Aisin 6 speed AW-F21 others I look out for
2007 Escape 2wd (the mini Pumpkin), 3.0L Duratec, CD4E
2008 Mazda3 5 door, 2.3L, 5 speed manual
Sorry I forgot to mention I had checked the Inertia switch right off the bat. I always figured it was best to check the simplest parts (switches) before tearing into motors or pumps.
I removed the input line to the fuel filter and tried KOEO and cranking. That should have made a huge mess all over the garage floor, I almost wish it had.
I checked a little closer, and it looks as though the fuel pressure regulator is an electronic unit. I was looking for a vacuum controlled unit with a dashpot or something obvious like that. So far I haven't found any method to check the unit, but I'm open to suggestions. It looks as though the PCM should throw a P0190-P0198 code if there is an issue.
I believe when the ignition switch is first moved to the on position the fuel pump relay's 2nd circuit sends a signal bypassing the PCM to prime the fuel pump. I think since it is separate from the PCM the fuel pressure regulator would not have any control of that function. I don't know for sure, but that's how it reads to me.
...I checked a little closer, and it looks as though the fuel pressure regulator is an electronic unit...
That is the "returnless" fuel pressure electronic regulator.
Quote:
...It looks as though the PCM should throw a P0190-P0198 code if there is an issue...
Not necessarily. IIRC, the PCM just "assumes" that it is working (i.e. there is no communication back and forth).
Quote:
I believe when the ignition switch is first moved to the on position the fuel pump relay's 2nd circuit sends a signal bypassing the PCM to prime the fuel pump. I think since it is separate from the PCM the fuel pressure regulator would not have any control of that function.
Nope. As soon as the key goes to ON, the PCM starts up and turns on the fuel pump via the electronic regulator. No fancy bypassing.
Maybe someone else has a wiring diagram.
__________________ Peace, it's our only chance
1998 E150 Club Wagon, 4.6L Modular, E4OD
2007 Milan. 3.0L Duratec, Aisin 6 speed AW-F21 others I look out for
2007 Escape 2wd (the mini Pumpkin), 3.0L Duratec, CD4E
2008 Mazda3 5 door, 2.3L, 5 speed manual
I have tested the fuel pressure at the fuel rail (there is none), the fuel pump fuse and relay (both work), and checked for voltage at the last connector to the fuel pump near the left rear tire (10.5v or so KOEO). I can not hear the fuel pump turn on with the KOEO at all
That voltage is a little low. Shouldn't it be the same as your battery voltage?
ALso did you check the ground?
If you are getting voltage to the pump, AND have a good ground it should turn on.
You may want to try running power and ground directly from the battery to test the pump to see if it will turn on.
If you need a wiring diagram, Autozone usually has them online in their troubleshooting section.
__________________
BroncoJoe19
2006 Alt Fuel Jeep (electric)
'98 windstar 3.8L
'99 Crown Vic 4.6L
'90 Full Size Bronco 5.0L
I'm not a professional mechanic, take my suggestions with a grain of salt, or a cup of coffee
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02 expedition will not start, All Fixed see post 16. 
Hybrid Mode
