Odd issue of not starting.

Drove my truck this morning, nothing out the ordinary, quick trip to town and back then parked it. Around lunch time I loaded up the family for an outing and the truck would not crank. It would turn over just fine but never try to fire. I reloaded the tune out of desperate measures and willing to try anything, but it didnt change. Shifted it from park to neutral back to park and tried again...no change, just turned over without firing. So out of frustration I left it sitting in the driveway, loaded up with the family in the wife's car and left for the day. Seven hours later we get home, I grab my keys, head out to the driveway and hop in. I cut the key on but didnt crank it, just shifted it out of park and all the way to first and back. I turned the key over and it cranked like nothing ever happened. Now I'm paranoid that this is probably not going to be an isolated incident. Anyone have a problem like this? I tried to be as detailed and descriptive as possible about what happened.

Any CEL's?

Maybe a fuel pump issue?

Maybe canister purge valve?

How full is your fuel tank, and what kind of angle was the truck sitting on while parked?

Who/What tune are you running?

Just some foods for thought....

No CELs and the driveway is fairly level. I'm running the svc tune and I reloaded it earlier with no success to the cranking ability. Tank is about 3/4 full. I'm on the fence about taking it to the dealer. If its starting and operating correctly will they be able to diagnose a problem that doesn't show up?

I'm thinking a possible ignition key problem. Did you try your other spare key? Or the ignition switch itself possibly.

Kevin did you have the Svc tune and return to stock then have a starting issue? Is the truck running now? Call or text me 9516754118 and We will get it figured out. Could be as simple as the sct device firmware was not up to date

I dont think its tune related, I just tried something, anything, to get it to fire. I un-installed and reinstalled just to cover that ground and there was no change. That was this morning, this evening I just stuck in the key turned to on without cranking, shifted all the way down to first and back to park then it started right up without an issue. I even shut it off and restarted it several times to try and replicate.

I asked our tuner and he said he's never heard of this. As haynes said I would check the canister purge valve. Can you hear a ticking sound by chance?

I just went outside and started the truck up, no ticking sounds that I can hear but consider it has a very loud cat back exhaust and i'm almost hearing impaired. It would have to be one helluva tick for me to hear it. Considering the possibility of it being the canister purge valve, is this something I could test on my own or would it be best left to a dealer?

Maybe put your hand on it and see if you can feel the ticking. The dealer won't replace this item because it will not throw a code. 55 bucks at the part house and 10 minutes worth of labor at most and you should be good to go.

-Jeff

so to clarify, when you tried startig thetruck, it would crank, but not start?