Cranks But No Start

[GZ123]

After resolving EGR issues and broken mega fuse in November, my 1998 XLT 4.6 4wd is down again.

When I turn the key the starter turns, but the engine will not fire. Things I know:

1. No CEL, and no codes or pending codes
2. The starter is brand new
3. There is fuel in the rail. I checked this by pressing the valve with a flathead, but do not have a fuel pressure gauge.
4. I pulled a spark plug wire and threw an old spark plug in and cranked and see no spark
5. I checked all of the fuses with a multimeter and all have continuity
6. Most importantly, I've got two deer tags and having a functional 4wd would greatly increase my odds of filling them

Any advice would be much appreciated. I'm really hoping this is a simple relay problem, but not exactly sure which one would be the culprit for my scenario. I have the version 1 box shown below:
https://fusecheck.com/ford/ford-expedition-1997-2002-fuse-diagram

Directly next to the box described in the link above, is another box with a bunch of relays that I can't find any information on.

 

[Killer Ride]

Could be a bad crank sensor

Sent from my SM-G950U using Tapatalk

 

[GZ123]

Killer Ride, thanks for pointing me in the right direction. So I plugged in my OBDII reader and when I crank the starter I read 0 RPM. I think this means that you're right and my crank shaft position sensor is dead.

Luckily it's a cheap part and not too much work to swap. Before I order it and replace, I want to eliminate another worry I have about the truck. One, or both of the timing chains are definitely sloppy. At high RPM I can hear them slapping. Could the 0 RPM with a starter crank and no spark also be indicative of one of them having jumped or fully broken? The truck never died while running, so there wasn't evidence of that catastrophic of a failure. It simply wouldn't start in my driveway one morning, but I'm not sure how to diagnose or I guess not diagnose a broken timing chain when I have this combination of issues.

 

[riphip]

Could very well have jumped time but unlikely. You should get some kind of rpm reading from your crank sensor if engine is turning.
Engine usually jumps time when it is turned off & stops abruptly. Chain or belt skips cog teeth from being too loose & still moving when crankshaft stops.

 

[GZ123]

New crankshaft position sensor swapped in this morning and she's good to go. Thanks all.

For future troubleshooters:

I bought this: https://www.amazon.com/Delphi-SS10875-Crankshaft-Position-Sensor/dp/B00EAMBMTW


And did this *they have the fan cowling removed in this video which makes the area around the AC compressor look more open than it really is when you get under your truck. I left my fan cowling on and still got all the parts out and back where they're supposed to be.