Engine Dying on Initial Startup

I am having an issue that started about a week ago from what I can tell, where I get in the truck (2012 DCSB TRD Offroad) after it's been sitting for a little bit, and I turn the ignition, the engine cranks and turns over, then dies less than a second later. If I try to start the truck again a second time, it will start up like normal, runs no issue. This has happened now 3 or 4 times in the past week.

Shortly after I noticed this start happening, I discovered the alternator had failed - I pulled and replaced with a new alternator this week, and confirmed it is working as it should now. The battery is fully charged and good to go. But the problem persists.

Right now I'm thinking there is either an electrical issue with the ignition, causing the truck to turn itself off, or an issue with the fuel pump but has anybody experienced this before?

Edit- Truck has about 47k miles on it for reference, but I do like to get muddy.

 

Is the check engine light on?

 

No, there are no lights on.

 

It’s possible it might be a fuel issue. You’d have to check the pressure after it sits for awhile. And Toyota didn’t make it easy to hook up a gauge.

My truck will do this maybe once a year.
Actually, it’s been a good while now since the last time. So I am probably due for it to happen soon.
No idea what makes it do it.

 

Am curious to see the responses here since mine does it from time to time as well. I assume it's a fuel pressure thing and the pressure bleeds off after sitting for a while.
I'm currently at 132,000 miles and ALL of my maintenance is up to date and my truck runs perfectly (as far as I can tell).
The last time it started doing it with some regularity, I used some fuel system cleaner and it seemed better for about 6-8 months. It's doing it again occasionally now but like you said, only after sitting all night in the garage or all day at work.

 

Yea it seems to be related to the initial fuel pumping, either the line not holding pressure from previously for some reason or something restricting the initial flow when the pump kicks on. When I start the truck, if I turn the key to ON for a few seconds first, I can hear the fuel pump kick on and then the truck starts and runs no issues.

 

I don't think the pumps start running until you crank the engine but I may be mistaken.

 

Ive seen this happen from time to time with my 2013, and as far as I can remember its after its been sitting for days. Maybe when I've had to jump start it.

 

I work on a lot of Tacomas and 4runners. When I disconnect the battery (2nd and 3rd gen), most trucks do this. Starts up, then dies right away. 2nd start is normal, and they don’t have an issue after that.

Maybe check connections again at battery and alternator. Make sure all are clean and tight.

 

Clean the throttle body

 

That's good to know, I've been taking the battery in and out a bunch so that could explain why. Will see if I have the issue pop up again.