i drove the truck all day today and everything was fine. i went out for the night and i was doing about 30 mph and the truck just shut down....all the lights and radio stayed on, i pulled over put it in park then turned the key and it fired right up and i drove it over to my buddies house to look at it...well we had the hood poped just looking at it and it just shuts off for no reason sounds like somone is turning the key off....i have no idea what this could be??? when its running its fine as could be it just decides to shut off when it wants and ideas?? thanks

 

crank sensor or coil would be the 1st places to start... I've only heard of a few coils being bad... most of the time it's the crank sensor.

welcome to DF...

 

what year, model, and milage?

 

1997 4x4....160.000 miles

 

fuel pump or clogged filter?

 

yeah idk i started the truck and went under it put my ear up the gas tank and listened to the pump run and when the truck shut off after about 10 mins of running the moter shuts off before the fuel pump does, when the truck is running its runs like its brand new and i could drive it at 80 mph and its fine its almost like a sensor kicks it off...it doesnt run rough or any thing before it shuts off, just sounds like someone turned off the key.

 

the in-tank fuel pump should be a suspect for the problem.

I suspect that the electric motor running this pump has a thermal cut-out that resets itself quickly when the ignition key is turned off....but it may be that when the suction filter at the very bottom of the assembly gets clogged with enough gunk the pump 'cavitates' and fuel psi drops suddenly and won't come back until the pump is turned off briefly.

I have an old 1995 fuel pump assembly that I intend to cut open the fuel pump and regulator on to look over, but I have not gotten around to it.

 

so today i went out to start the truck up to go to auto zone so they could run there free check on it to see if it was running a code well........so i started it up in the drive way so far so good, then drove about 700 feet and it shut off on me...no warning it just seems like somone turns off the key, pulled over restarted it and wnt about 4 more mins then shut off..it did this about 5 times in a 10 min drive....finaly it shut off and i could not get it started again, so i had to have it towed to the dealership that is closed...soo my ? is does this sound like a crank sensor or what ivebeen reading on other topics and i guess it could be alot of things....i do know that the fuel pump does turn on when i turn the key and stays running whenthe truck is running butwhen the moter dies i can hear the pump run about 2 secs after the moter shuts off? so its seems like its working....idk what to dowith this problem i have to call tom morning to the dealer ship and explain my problem i just hope this bill is not to big....thanks alot

 

did you swap the crank sensor already? or the coil? they are 2 easy swaps, the coil being really easy neither part costs more than $50~60 bux.

 

no never had the chance...haha i broke down before i made it to the auto parts store...tom when i call the dealership ill have to tell them what i think it needs...