Hi folks!
Thanks in advance for any help offered and questions answered!

Our '01 V10 6.8L Excursion won't start in my daughters after school class parking lot.
The proprietors are being really nice about it, and there is a lot of available space there, but I don't want to take to long too diagnose this, so I am reaching out to you guys for help.

My wife reports that for the last few days it has started kind of sluggishly, and has idled a bit low.

How it stopped working:
Wife has been driving car in the morning to get to work, and now after work OK.
We drive to our daughters class to drop her off (about 1/2 mile away).
We get back into the car, and try to start, but the car cranks, but will not start running.
It sounds a little weird, like it is cranking *too* fast.
It seems like it will almost start sometimes, but then it doesn't

So we switch drivers and I try to start it.
Same deal, it sort of acts like it is about to start, at ~500 rpm on the tachometer, and then just completely dies.
I wonder if the big dip outside the class parking lot maybe tripped the fuel cutoff, so I try to reset it. It feels like maybe it moved a little-maybe I am just too hopeful.
Now I try to start it, and it almost starts
It sounds almost right, gets to about 1000 rpm, and then dies like before. Not sure if fuel cutoff reset attempt is related.

I try to off-on cycle a few times making sure I hear fuel pump, and trying to get pressure in the line.
I DO hear the fuel pump.
Can't be sure there is any difference in starting the car.
Car alternates between almost starting (1/5 of the time) and sounding like it is not having any of this (4 /5 of the time)
I try to floor it while starting it, holding the gas pedal fully down--as dad taught me to
No change.

Recent maintenance:
I replaced the battery (pro-rated warranty for the second time in a row) about a month ago.
I replaced the fuel filter at 200,000 miles. (20,000 miles ago)

I read related posts on this forum last night and the summary was this:
Pull Codes -- I bought one last night at Harbor Freight, and scanned the codes this morning. No DTC codes were set (but the IM test had some stuff red-Xed, I am not sure if the reading works without the car running though)
Check fuses and relays (checked all fuses in the passenger compartment fuse panel this morning, cigar lighter, data link connecter was bad, so I replaced it to scan codes with) I will check power distribution boxes later today.
Check fuel pressure or spray starter spray into air intake (haven't done this yet - have starter fluid already though)
spray-clean IAT Sensor with carb cleaner (haven't done this yet - have carb cleaner already too)

Likely causes in rough order of frequency mentioned:
Fuel Pump
Fuel Pressure Regulator
Fuel Pump control Module (if equipped)
Wires to the previous three items.
cam position sensor (should set a code if it is bad)
crank position sensor (should set a code if it is bad)
other sensors

My Questions:
Wouldn't low fuel pressure set a code?
Since there was no codes set, then doesn't that suggest a problem on the sensor/air flow side?
Should IM tests tell me anything valid without the car running about sensors, etc?
I have a fuel pressure gauge, but I am not sure where to connect it. Normally I expect a schrader valve on the injector fuel rail or something, but I didn't spot it last night. Where is the connector? If no code is set, could the pressure be low?

Thanks for your time!

 

Make sure PCV is properly seated and there are no other major vacuum leaks. Mine did this but eventually after sitting would start. Then after driving for several hours and having lunch and trying to start it again it would only crank...no fire.

In my case the PCV heater loop was under the ridge of the PCV keeping it from fully seating. Big vacuum leak!

 

Low fuel pressure wont neccesaraly set a code. Check the fuel pressure. Schrader valve is on the fuel rail, I think on the driver side. Also check to see if you have spark.

 

OK, I went back last night, and:
The PCV was seated solidly
Didn't spot any problems with vacuum lines.
Checked all fuses relays and diodes in the power distribution box, and all were good
Then I sprayed carb cleaner on the IAT/MAF - no change
Then I sprayed starter fluid into the air intake tube (past the MAF) - the car tried to turn over, so i figured this eliminated spark.
Then I checked the fuel pressure as sccamper suggests - no pressure!!!

This morning I towed it to my house so at least that concern is taken care of.

So now I am down to the fuel system, and I think it can only be the 20,000 miles on it filter is blocked, the fuel pump has failed, or the fuel pressure regulator has failed. It could be the FPCM people mention, but I don't know if my 01 X has one of those...

How do I test this to isolate which of these fuel system components has failed the quickest. I don't want to replace one of these, and find out that I replaced the wrong thing. Or should I replace everything? Thoughts?

 

Bad pressure regulators usually cause pressure to be high or will leak. Test the fuel filter by taking it off and blowing through it. Sounds like it may be a bad fuel pump, not uncommon. Need to make sure you have power and ground to the fuel pump.

 

Since the weather was great today, I went outside, and got ready to empty the fuel tank since I figured I would need to to replace the fuel pump. Started putting the siphon tube into the tank and decided to give it a try--just in case the car was happy with the nice day.
Car started after a couple of tries.
Took out the siphon, and drove it in front of the garage.
Sat watching the OBDII scanner, on live data and still no codes.
BUT the idle is VERY inconsistent (500-900 rpm).
I checked for misfires, and there were none.

I will start checking the fuel lines and electrical connections, but I hoped this sounded familiar.

1. Wouldn't start in the middle of the day
2. Wouldn't start at night -- no fuel pressure.
3. Added 10 gallons to the tank and a half can of seafoam -- still no fuel pressure
4. Towed it home, let it marinate for two days
5. On a nice warm (+45 F) day, car starts.
6. Idle is inconsistent, with no misfires.

 

Dying fuel pumps are known for this behavior, work when they feel like until they work no more.