Lately I have had my 2000 Sierra 5.3 acting up, once in a while it will start and die, idle is low 500 sometimes 300, I can keep foot on gas to keep runnung, when I let off it dies,after a while it will straighten it self up, seems to be getting worse, any ideas? Thanks

 

a few possibilities...idle motor...tps...

gm had a reflash for this as well

 

Thanks I will check those, I was also told, it was being stupid due to a battery that went dead and it neededthe pcm torelearn the idle, I followed the GM procedure process of running in drive with e-brake on & a/c off for 5 min, then in park for 5 min, then shut off for 30 sec, also cleaned throttle body with brake clean and a brush, hopefully that worked, if not I will check the others and let you know, I guess this can happen anytime you change the battery or disconnect the battery