No crank issue on 2004 Ford Expedition NBX 5.4 First some background into the problem and follow ups done. Over two years ago I began having...

No crank issue on 2004 Ford Expedition NBX 5.4 First some background into the problem and follow ups done. Over two years ago I began having occasional no crank issues with the vehicle. At that time, usually it would crank and start after waiting a few minutes or so. Over time the no crank issue became worse. It other words, it became more frequent and often had to wait longer periods of time for it to start(crank). Sometimes I even had to wait for the next day to get it started. Eventually, the no crank issue seem to reach a critical stage, in which I installed a new starter and new ignition switch. A new battery was installed shortly before that. After installing these new parts, the vehicle started for just a few times, and I encountered the same no crank issue. In an effort to explore other possibilities, I wondered if the ignition tumbler was the problem. Coincidently, at the point I happened to pull the tilt steering all the way down and the vehicle started. I put it back in the full tilt up position and the vehicle would not start, but when I would put the steering down, it would crank and start normal. I continued using the vehicle for a few months but eventually no matter how the tilt steering was positioned the vehicle would not start. One time only, I grabbed the wiring harness under the dash and the vehicle started up. However, the next time I tried to start the vehicle, it would not crank, no matter what I tried. In February 2017, I tried the vehicle and it started fine every consecutive time for about a week, as I moved it in and out of my garage to be able to work on my wife’s car a few times. However, after about a week or so, I couldn’t get it to crank, on numerous daily attempts. I began to perform a few troubleshooting tests, and even removed the remote starter, just in the off chance that it was causing a no crank issue. However, it did not solve the issue. At one point I touched the relays in the passenger side kick panel area, to feel for the click, and at the same time turning the key.
The vehicle suddenly started, and I did this 3 or 4 times over a few minutes period, and each time I would do this the vehicle would crank and start normal. However, I’ve had no luck getting it to start since.
I removed the Central Fuse Panel just to check if anything seemed burnt, damaged or corroded, but everything looked perfect. I checked a few things with the test light, as follows: The constant power wire at the ignition switch tested okay. The crank wire at the ignition switch (with the key to start position) tested okay. The started relay tested with power on pin 30 on the fuse panel. With the key in start position, no power on pin 86. I’m still thinking there may be an open somewhere in the wiring under the dash, or a grounding problem, as the odd cranking situation seems very erratic. Also, the dash lights acted different than normal during this no crank, and sometimes the radio would power on when trying to crank. Is there any way to direct wire to the starter, or what would be the next steps or tests to perform to troubleshoot this issue? I would like to begin troubleshooting the vehicle again on Monday, April 17, 2017. Any help would be appreciated.

Thank you Relly.  I am in the Newfoundland Canada time zone.  It is just after midnight here now.  I will be looking at the vehicle on midday Monday.  However, I am not a mechanic, but I have never heard of a crankshaft position sensor preventing the motor from cranking.  I know it can cause a motor to stall or not start.  Also , the vehicle has never stalled on me. and there are no engine codes, as I have checked for engine codes. In all the history of owning the vehicle, whenever the motor has cranked, it has started. I've had the vehicle for about 6 years.

Howver, I have never replaced the sensor. If you are sure a bad CPS can prevent a motor from cranking, I would be willing to install a new one.

Thank you. I will purchase a new crankshaft position sensor sometime this week and have it installed.  I will keep you posted on my progress.  I have a one-way drive of about 1.5 hrs to purchase auto parts... I live in a small town rural area... Kind Regards.

The issue I am having is the engine does not turn over at all. Any time I can get the motor to turn over, it will start up right away.  As I said earlier, I tested the 12v constant power wire on the ignition switch, and it tested fine.  Also, the power wire for the crank signal also tested fine on the ignition switch, when I turned the key to the crank position. I don't understand much about the shifter assembly or the safety neutral switch, however, I have also tried cranking the motor with the gear shift in the neutral position, but no success in getting it to crank. Thanks for the advice. What is the procedure for accessing the the shifter assembly, as I have little to no mechanical experience. Thanks.

Thank you very much...this information seems very logical and helpful...However, I am a kindergarten student when it comes to mechanics. lol

So, pin85 is the ground of the relay...  All of my previous tests were done using the test light, however, I could use my multimeter instead. Sorry, not exactly sure what I am suppose to do, as I don't want to damage anything.  So, am I understanding this correctly; I could use the ground of my test light on pin 85 position on the fuse panel, and then put the probe on pin 30, which has power, even with the key in the off position.  If this is correct, good....but what would i do to try with the key on? Same thing?   I am doing this with the relay out, and using the pin positions in the relay slot?  Thank you....

Thanks...I will definitely try that, and update here...Regards.

Thank you Gord....I have now determined that there is no ground on the starter relay; pin85.  So, are you telling me, this is where the fun begins? lol  Anyway, what does this mean exactly?  I did make an error below though...there is no power on pin 30 with the key off, key has to be in on position.  Also, I just tried all positions of the ignition key when testing for the ground on pin 85....    Thank you very much for that help....at least now there's some progress in resolving this brute of a problem...lol

    Thank you all.  I expect to be out of town for a few days beginning tomorrow, so my troubleshooting will resume when I get back...I guess my next issue is determining where the ground feed is for the starter relay in the central fuse panel.... Regards.

I will be back home sometime next week... Any advice on troubleshooting the ground for the starter relay fuse?