I thought my key cylinder was bad, so I took it apart and cleaned it with contact cleaner. I also found that the wires that lead into the plug that goes into the crank sensor were twisted and bound and chafed in a few spots. I fixed all that, and the engine started up fine for about a week. The intermittent starting problem came back. I realized now that I couldn't hear the fuel pump kick on when I turned the key on. I wacked the bottom of the tank with a rubber mallet and then it started right up! That led me to believe that the fuel pump was getting stuck and wouldn't kick on when I turned the key. I think there is a bad spot in the fuel pump motor, and after it sits up overnite, it must've been seizing a little. It always started with the help form the hammer. I replaced the fuel pump 5 days ago and haven't had any starting problems since. I think that was my problem all along (knock on wood)!!
Well, the truck has continuously started without any problems since my last post a couple of weeks ago.
Actually, I never installed the cranking battery. I wanted to wait until such a time where I had another "no-start" situation and I could immediately remove the battery and have it tested/checked right at that point. Well, I think I "scared" the thing because with the cranking battery sitting in the passenger seat floor area, it has started on the first try ever since. I've had a meter connected to the battery since as well, and each time I try to start it now (every few days or so, trying to get it to fail again), the voltage is approximately +12.4 VDC or greater before turning the key on. After I turn the key, I can hear the pump run, so I know that it's going to start for me. Voltage immediately goes up to over +14 VDC upon starting and continuously shows right around that level of charging/voltage present.
cstrack - no worries, I'm an engineer also. There is nothing worse than to try to solve or troubleshoot a problem that is intermittent. Just when you think that you've solved the problem, it can show up again when you least expect it. Still, I'm not sold that it's completely a battery problem, but I agree, if I can get by without having to replace a pump, then that's a bonus for me.
I am in the process of trying to sell the vehicle, so I'd like to be able to say that it starts and runs without problems with confidence. I won't ever try to "hide" any problem like this from a potential next-owner of my truck.
Thanks again for all the advices everyone. I'll continue to post on the status and progress of the no-start situation.
Sorry it has been a couple of months since my last post everyone, but the NO-START problem that I was experiencing NEVER RETURNED!!
I have since sold the vehicle and informed the buyer of everything that I'd been experiencing with the truck and the no-starting problems. I had connected my DVM to the battery and ran the leads inside the vehicle in order to monitor the battery voltage at all times, from the initial turning of the key, to the cranking, and finally starting and running voltages. They all were "normal" after the initial "jump-start" that provided my battery with enough voltage to start the engine.
It seems as if the PCM required more than +12VDC to "tell" the fuel pump to operate during the start cycle. Or, it could be a bad "spot" on the fuel pump motor, and it simply has not "landed/stopped" on that one bad spot again.
While I still owned the vehicle, I would occasionally start the truck and drive it around, running errands, etc. wondering whether or not the "no-start" problem would decide to return after stopping the engine in a parking lot or something like that.
Thank you to everyone for your comments and your knowledge and suggestions on this problem. I hope that my documentation can help another person with this problem sometime in the future.
To reiterate: my solution was simply to charge the battery to it's full potential, which made the no-start (no fuel pump operation) go away.