You have to charge the battery up before it will idle. These trucks must a a certain voltage to the PCM for them to run if you left the cables on until it was charged a bit more it would be fine. I agree with the others it sounds like your TPS is toast.

 

^ yep. proper idle requires fully charged battery...
your plot is pretty hazy right now, but since you need to spend time charging your battery, you might remove your old TPS and blow out the moisture with air or wd40. it might work ok when dry.

my previous tps episode was surging idle on in cold weather. it didn't matter if it was wet or dry, just cold. it would rev up to about 1500-2000 at startup, and then sit there and surge between 1000-1500 until it warmed up, then it would act normal. the worst thing is that i'd change the IAC and reset the PCM, which would cause it to work ok for a day or two or a week (until next cold day), and then it would start doing it again. i tried to make it an IAC problem and changed it 3 or 4 times. it was the stupid TPS all along.

 

Ok. I replaced the TPS with a BWD TPS from O'Reilly's. This one came with a gasket (what a novel idea). I installed it, started it up....and it ran a little rough (low rpm's) after about a 30 seconds. I few revs and running it at 2500rpms later, and it was idleing right below 1000rpms just fine. I even ran it through the car wash and not once die the rpms drop. Don't know if I will get another cold morning to check the TPS running under cold conditions, but I am 85% confident that the TPS was the issue.

Thanks for all your help!!

 

Just disconnect the battery and charge it at 20 amps,When batteries in these trucks die down they make the computer act strange,I think it has alot to do with the regulator built in the computer unless the batery is fully charged it won't run right.