My Truck won't stay running without throttle
#12
glad you got it running.
i'm going to guess at what was happening... something in the pcm and sensor circuit is probably expecting a voltage signal based on a 12 volt baseline. a bad battery with one or more dead cells, is registering about 11 volts or so. you manage to get it cranked and it runs. the alternator is pumping in voltage thats just getting sucked into the black hole of the battery. a key sensor, maybe the tps or iac, gets a reduced voltage signal, which just screws up everything.
i'm going to guess at what was happening... something in the pcm and sensor circuit is probably expecting a voltage signal based on a 12 volt baseline. a bad battery with one or more dead cells, is registering about 11 volts or so. you manage to get it cranked and it runs. the alternator is pumping in voltage thats just getting sucked into the black hole of the battery. a key sensor, maybe the tps or iac, gets a reduced voltage signal, which just screws up everything.
#13
glad you got it running.
i'm going to guess at what was happening... something in the pcm and sensor circuit is probably expecting a voltage signal based on a 12 volt baseline. a bad battery with one or more dead cells, is registering about 11 volts or so. you manage to get it cranked and it runs. the alternator is pumping in voltage thats just getting sucked into the black hole of the battery. a key sensor, maybe the tps or iac, gets a reduced voltage signal, which just screws up everything.
i'm going to guess at what was happening... something in the pcm and sensor circuit is probably expecting a voltage signal based on a 12 volt baseline. a bad battery with one or more dead cells, is registering about 11 volts or so. you manage to get it cranked and it runs. the alternator is pumping in voltage thats just getting sucked into the black hole of the battery. a key sensor, maybe the tps or iac, gets a reduced voltage signal, which just screws up everything.
I've got a sneaking feeling we've not heard the last of this.
#14
yes it should. a properly working alternator should energize the entire electrical system to about 14 volts. but several people have posted this problem over the years, a low voltage condition is the only thing i can think of.
i don't think its the pcm reset, because that usually fixes problems, not cause them.
and then when they replace the battery - poof its fixed.
here's one last reason why i think its a low voltage condition. have you ever tried to jump another vehicle, and you hook up the cables and the other vehicle just clicks... and so you jiggle the cables around and reclamp them several times - clicks. so you crank you truck and rev the motor - still clicks. so you rev the motor for 5-10 minutes and it still clicks. the other vehicle's dead battery just acts like a black hole of electricity. and after you get tired of screwing around you go buy a new battery and everything works fine.
i'd bet that if he was to check voltage on his dead battery with engine running, (that somehow, idk) it would not read 14 volts from the alt, but would read low.
i don't think its the pcm reset, because that usually fixes problems, not cause them.
and then when they replace the battery - poof its fixed.
here's one last reason why i think its a low voltage condition. have you ever tried to jump another vehicle, and you hook up the cables and the other vehicle just clicks... and so you jiggle the cables around and reclamp them several times - clicks. so you crank you truck and rev the motor - still clicks. so you rev the motor for 5-10 minutes and it still clicks. the other vehicle's dead battery just acts like a black hole of electricity. and after you get tired of screwing around you go buy a new battery and everything works fine.
i'd bet that if he was to check voltage on his dead battery with engine running, (that somehow, idk) it would not read 14 volts from the alt, but would read low.
#16