Hey guys new member here with my first post. I have a 2000 GMC Sierra 4.8L 4WD 5speed manual with 90K miles. I've been having problems with it stalling?? when its cold. It starts fine and idles normal but when a head down the road it acts like its flooded past half throttle, but seems runs fine if I keep my foot out of it. It goes away after a mile or so then runs fine. I recently changed the air filter and fuel filter but was thinking maybe new plugs might be the next step?? Any ideas

Thanks

 

Yeah do a full tune up wires plugs maybe throttle position sending unit if you still have problems try egr valve them move on to muffler
All will make it run like crap good luck