Start for sec then die.. *read*

[fdchief]

i need some help here folks... here are the symptoms... when engine is cold.. itll fire run for a second(literally) then die after i do this a few times it will stay runnin.

now i dunno if this has anything to do with it but it got cold last night (20 degreees) and i forgot to turn on the block heater. also the batteries were dead when i tried to start it so ive replaced both batteries today. I will also add when i jumped it off today i was crankin on it hard before it started. Im stumped any ideas?...

[m-chan68]

Have you had the truck scanned for codes yet? If so, what codes were retrieved? What is the ambient temperature where you are located?

[fdchief]

not scanned yet.... it was around 25* when i tried to start it this morning...and after i finally got it started.... it ran fine... went in town ran a few errands ran fine....stopped at a place for a about an hour and a half came out and it would crank fine start then just die. after about four times it finally fired and ran like a champ. when i got home i turned it off and restarted it about 5 times.. each time it fired right up...

*update* i just went out and tried to start it and it fired right up. its been sittin for about 3 hours with the block heater on.. the temp right now is around 22*

[greasltn]

How long since you changed the oil. I had a friend that didn't change his oil until the truck wouldn't start. Needless to say his truck didn't last long. Also check the oil level.

[fdchief]

oil was changed 2 days ago....

[greasltn]

sounds like the HPOP is going bad. But you need to scan for codes before we condem the HPOP.

[fdchief]

*update*... it sat all night. and all day today.... after tryin for about 10 mins of crank-fire-die..... it finally fired and stayed running..... takin it to the dealership in the morning.....

[pinkfloyd]

did you have it plugged in? it's gotta be cold there. How many time do you cycle the key before you try to start it or how long do you wait to crank. When it gets cold out I wait about 30 sec. before I crank the motor reguardless of the wait to start light.

[fdchief]

Originally Posted by pinkfloyd

did you have it plugged in? it's gotta be cold there. How many time do you cycle the key before you try to start it or how long do you wait to crank. When it gets cold out I wait about 30 sec. before I crank the motor reguardless of the wait to start light.

yes it was plugged in...and i wait until i hear the "injectors stop cycling" and the glow plug light is out. temps have been steadily in the 20's here.

om a side note.. with it plugged in what should my oil temp and coolant temp read when i go to start it... the oil almost always reads close to ambient temp myabe a lil warmer and my coolant always reads around 140..... this is on my bullydog outlook monitor of course

[fdchief]

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Ok well i kinda have it pin pointed and i hope my descriptions will make it easier for those more smarter than i...

Symptoms: truck will turn over fire then die repeatedly before finally firing and running as if nothing is wrong. this has been going on for a week. this is only when the truck is cold.. if it is warm it will start right back up.

Now here is where i think i have pinpointed the problem.. just not sure what it is. when i go to start the truck you get the usual injectors cycling as well as a louder hum(not every time) and a lower toned hum as well. I have noticed every time when i try and start it.. if i dont here the "quieter" or lower toned hum it will not fire but as soon as i hear it it will fire.

My question is what is the "quieter hum" that turns on when you go to start the truck?

Any and all help is beyong greatly appreciated....