Okay ive got a 98 ls 4dr 4.3L here in Minnesota where the temps have been really cold the last couple days. the first problem was occasionally after starting up the car it would die was soon as it was taken out of park but would typically run just fine in park and it would also die sometimes while in drive at low speeds. I was able to prevent this by holding the brake down and giving it some slight acceleration before shifting from park. in the last couple nights the temps have been way below zero with the windchill here and i just cant seem to get my car to start up anymore. its got a block heater hooked up to try to help with the low temps, the voltage meter is half of normal running voltage with the key turned, i can hear the pump turn on, the service engine soon light stays lit as i turn the key over, it cranks but just won't seem to fire. could my no start just be due to the cold weather or is there possibly something else going on?

 

I had the same thing a month or so ago. Believe it or not, all I could find wrong was dirty battery cables. It would start fine, but wouldn't stay running without some foot. It did this for a couple of days, and all I did was clean the cable ends, and it stopped, and hasn't done it since.
I know it doesn't make much sense that it had juice to start, but not to idle. I guess maybe the connection was a intermittent, and not feeding steady voltage to the brain.

 

Yeah ive definitely had some problems with corrosion in the past, but i checked it out earlier and they all looked fine. how high is the voltage meter supposed to be with the key in the ignition, i know it goes up to the normal 14 volt range when running but should it only be about 11 or so when trying to start it?

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after charging the battery last night, i went out this morning to some warmer temps (20 degrees) and put the battery back in, it fired up almost right away, and died shortly after starting. started it again and this time held a slight rev to the engine for about a minute with the truck running but as soon as i let off it died again. now its doing the same thing as before just cranking but with no fire. its a brand new battery, my previous one tested bad a couple weeks ago, could this one be bad too or is there something with my truck that is possibly making them die/go bad so quickly?

 

after charging the battery last night, i went out this morning to some warmer temps (20 degrees) and put the battery back in, it fired up almost right away, and died shortly after starting. started it again and this time held a slight rev to the engine for about a minute with the truck running but as soon as i let off it died again. now its doing the same thing as before just cranking but with no fire. its a brand new battery, my previous one tested bad a couple weeks ago, could this one be bad too or is there something with my truck that is possibly making them die/go bad so quickly?