coincidence ??? crank no start. Ignition vs. fuel pump

[rfm77555]

Would love any input or advisement.

2007 5.4 Triton never any issues until yesterday mornings crank no start.
Very cold here (as is elsewhere).
Turn of ignition and the key does not return to run from start position without my help.
In other words if I turn to start and take my hand away the engine continues to crank but never starts.
It has never done this before and I feel has to be linked to the crank no start BUT.........
I have previously owned for many years a 99 expy and had to replace twice the fuel pump on it.
Current situation makes me think same problem but the ignition thing has got me scratching my head.
Is there any way to easily get any fuel into the throttle body to see if she will fire ???
I have my son turn the key while listening under the hood and do hear what seems the normal fuel rail charge sound I am familiar with.
Laying under the vehicle with ear against the fuel tank I have my son again key on and nothing.....not a sound.
Not looking forward to dropping the tank to replace pump in the sub freezing conditions.
Am I crazy to suspect this ignition my be my problem ???

 

[JExpedition07]

Do you have your owners manual? Locate the fuse for the pump and Check that before you go throwing a new pump at it. I believe fuse locations are around page 290ish in the manual, might start on page 288. Fuses #18 and #62 under the hood are related to the fuel pump.

https://www.f150forum.com/f38/2010-f150-5-4-cranks-but-wont-start-290718/

Here is an 07 Manual, I linked it to page 290 with the fuse locations with regards to the power distribution box
https://www.manualslib.com/manual/616196/Ford-Expedition.html?page=290#manual

 

[Bedrck47]

You could get a can of starting fluid and spray a little into the TB while your son turns the key to the start position If the engine fires up for a short bit I would say you have a fuel pump problem or something electrical for the fuel pump

 

[Bedrck47]

Also Check fuse #32 and #71 under the hood

 

[rfm77555]

I did pull the fuse listed for the fuel pump (#32)....checks ok
The relay for the pump listed (#18)....I swapped it with the like for like at location (#19)....no change
However I did not check fuse #71. What is the fuel coil ISP-R ????
Thanks for the replies
I did also confirm the inertia switch

 

[gixer2000]

You could get a can of starting fluid and spray a little into the TB while your son turns the key to the start position If the engine fires up for a short bit I would say you have a fuel pump problem or something electrical for the fuel pump

Need some of this... But really after you try starting fluid and check those fuses you may want to try getting access the harness to check power before dropping the tank. I dropped a tank once before checking power at the harness only to realize I had a broken wire.

 

[Bedrck47]

Hopefully when you checked the fuses you used a volt meter and not your eyes

Looks do not make things work It takes voltage

If unsure how to test a fuse see the attached link

http://www.expeditionforum.com/threads/fuse-testing-101.24587/

 

[bobmbx]

Would love any input or advisement.

2007 5.4 Triton never any issues until yesterday mornings crank no start.
Very cold here (as is elsewhere).
Turn of ignition and the key does not return to run from start position without my help.
In other words if I turn to start and take my hand away the engine continues to crank but never starts.
It has never done this before and I feel has to be linked to the crank no start BUT.........
I have previously owned for many years a 99 expy and had to replace twice the fuel pump on it.
Current situation makes me think same problem but the ignition thing has got me scratching my head.
Is there any way to easily get any fuel into the throttle body to see if she will fire ???
I have my son turn the key while listening under the hood and do hear what seems the normal fuel rail charge sound I am familiar with.
Laying under the vehicle with ear against the fuel tank I have my son again key on and nothing.....not a sound.
Not looking forward to dropping the tank to replace pump in the sub freezing conditions.
Am I crazy to suspect this ignition my be my problem ???

\
Whoa...that is exactly what my Mountaineer did over last weekend. Cranks just fine, no start. And the starter stays engaged after taking my hand off the key (ignition returns to "RUN") for several seconds. Had it towed to the dealer....new fuel pump being installed.

 

[chuck s]

Neither my '07 nor '17 Expeditions require the key be held in the start position. Just twist and release and the starter will run until the engine fires. Key springs back to run while the starter is running. I assume this is normal and accommodates an exotic START button on some models.

The only access to the fuel pump requires dropping the tank. PITA. I had a wiring problem with my '07 a couple of winters ago when I was out of town. Momentary open circuit to the fuel pump. Fuel pump just shut off at speed. Five minutes on the shoulder and she'd run again. Did this three or 4 times one evening before I got her to the house and had Ford come and get her in the morning. Frayed wiring somehow.

-- Chuck

 

[Big Brian]

try swapping the fuel pump relay with another one from the fuse box. They should be the same. if it starts then you have a bad relay

 

[Boose]

My Taurus has a similar issue when really cold... Turn the key to Run and listen for the pump. I need to cycle my key 20-30 times sometimes to get the pump to kick in. Once started she's fine. I have done all of the tracing, relay swapping etc. I have a new ignition switch on order as everything else checks out fine. Above 20 degrees, and it never does this.

 

[rfm77555]

update:
Fuses all check okay (using a volt meter).
Already tried the relay swap.
Vehicle was pushed in to my unheated garage, I leaned cardboard all around the outside perimeter of the vehicle, aimed a propane salamander heater under and after 4 hours got a old mercury thermometer on the dash to move from below 15 up to above 35 degrees. At this point I tried to start and it at least fired (not even close to a start) but definitely more than just turning over. (the ignition key by the way, still stayed in the start position the whole time until I manually backed it off to the run position ????)

I still cannot hear the slightest sound at the tank (fuel pump noise)

fuel pressure check attachment point on the fuel rail......removed cover (looks just like a tire valve stem) depressed valve pin and the smallest amount of fuel came out but only once. I expected more pressure here ...am I wrong ????

Going to look for the power supply to the fuel pump to check for voltage there (any advise on this)

Does the power supplied to the pump go to the inertia switch first, as it is easy to get to to check there ???

After that I am gonna try the starter fluid to see if she fires and if so would more likely indicate a fuel supply issue correct ????

The air intake "plumbing" is such a pita....where to disconnect and spray a tiny shot of starting fluid ??? again the cold is no help here at all, everything is so brittle I hate to apply much pressure at any point.

thanks again for all the replies

 

[Boose]

Did you check the inertia switch?

 

[Clemson82]

I'd go straight for the starter fluid. How much gas do you have in the tank? With these temps, if there is water vapor in the tank or line, it could freeze things up.

 

[Boose]

There should be voltage at both wires on the inertia switch with the key on. If you have power in but nothing going out the switch is suspect. I am not sure where the fuel pump driver module comes into play regarding the flow however.

 

[Bedrck47]

Attached is a copy of the fuel pump circuit As you can see power comes from Fuse #32 Thru the contacts in the fuel pump relay

Then to the shut off switch and then to the fuel pump

Power for the coil off the fuel pump relay comes from fuse #71 and the coil is controlled by the PCM

 

[Bedrck47]

There should be voltage at both wires on the inertia switch with the key on. If you have power in but nothing going out the switch is suspect. I am not sure where the fuel pump driver module comes into play regarding the flow however.

The 07 doesn't have a FPDM

Also if the engine isn't running you may not see a full 12 Volts going to and coming from the shut off switch

This happens due to the PCM not sensing a running engine and limits power to the fuel pump so as not to flood the engine

 

[Boose]

The 07 doesn't have a FPDM

Also if the engine isn't running you may not see a full 12 Volts going to and coming from the shut off switch

This happens due to the PCM not sensing a running engine and limits power to the fuel pump so as not to flood the engine

Very good point! Voltage will be present for the prime only if she doesn't crank and fire up.

 

[rfm77555]

UPDATE

Thanks All for the information received.

So all things pointing to fuel lacking after spraying combustible aerosol into intake line and it started and stalled.

Dropped the tank and found fuel pump with obvious heat damage on the negative side.

Install new pump assembly, reinstall tank, and it started right up.

 

[East-TN]

Wow...that’s a little scary seeing that much heat damage. Glad you fixed it and are back running.