When I start our 1997 Blazer in the mornings & take the dog for his run in the desert, I find that if I stop & let the truck idle in park waiting for him, when I take off the engine wants to stumble sometimes it dies but starts right back up. Once the engine is warmed up to temp this never happens. It idles at 600 rpms, no codes, other than this the truck runs great we get 16-18 mpg winter time.
Can anyone give me direction on where to look?
Thanks, Craig

 

I would clean or replace the EGR valve, could be it is leaking some exhausts gas back into the intake system when it should not. My 89 S15 Jimmy was doing the same thing and I replaced mine with a GM EGR Valve and have not had the problem since.