Truck cranks, runs for a few, the shuts off...2007 5.7

just got home from work and i go to hook up my camper and my truck cranks fine.....runs for about 5-6 seconds and shuts off. does it over and over and now wont even crank. fuel pump? thinking it may have been cranking and running on fuel in the lines? now there is now fuel it wont crank?

 

ok. i go out about 15 minutes later and it cranks and stays running. so?????? security cpu.....geez i hope not

 

do you hear the fuel pump kickin in when you turn on the key ?

 

no but i has been running now for 10 minutes. turned it off again to try and hear the pump and i cannot hear anything....but it has been running now.....now i am afraid of getting stranded. a shop cant tell what it is doing if it wont do it. no check engine light is on

 

Could be electrical??

 

Fuel pump,relay to the fuel pump bad, crankshaft sensor not picking up.. or battery connections dirty not making solid connection..

 

fuel pump relay would be nice. but it wont be my luck

 

Rare relays go bad for no reason.. the Toyota fuel pump is a tough pump.. I have 280,000 on mine it's in my Tacoma tho..

If you know how to use ohms meter. Check for continuity between ground and where the lead going to the fuel pump is on the relay side.. if it reads infinity pump is shot... if it reads continuity pump is good...

 

taking it to my buddy who is going to test that stuff tomorrow...he can also test fuel pressure.....guess i will know more tomorrow

 

I don't know if Tundras use igniters but if so dbl check harness connections, they can seem tight but as I found out is not always true...

 

Reviving an old thread, my 07 5.7 does this almost weekly now but cranks on the 5th try every time. It has went into limp mode once after cranking it after driving it hard in an emergency. Would this be the aip or crank position sensor?

 

160k. I unhooked the positive battery cable and that cured the limp mode.

 

Mine does this as well. (2010 platinum with 225kms)
Mostly seems to be when there would be moisture around. Freeze/thaw/wash etc.
But if I wiggle things around in engine compartment fuze block, it seems to start next try. I have been applying dielectric grease to connections but haven't narrowed it down to one place yet
Interested to see if anyone else finds out anything

 

I have this same issue and I just unplug the positive battery for 15 seconds and she fires up every time took it to Toyota several times for this but they say they can't replicate it so I just carry a 10mm wrench on me to pull my positive and don't bother preset radio stations

 

I've come to wonder with mine, that it may have something to do with the key...
maybe not reading chip right...?
Could ignition switch become worn and cause this somehow? My truck has almost 230000kms so likely has seen its fair share of use