Tahoe trouble

My 2001 Tahoe never starts first try unless it is warm and if I hammer down to passing gear it bogs and hesitates and shifts hard. if I hit passing gear @ half pedal or less it shifts and runs out perfect. 1 1/2 years ago I did a tune up it has 120,000 mi with a 5.3 L :runaround:

My 2001 Tahoe never starts first try unless it is warm and if I hammer down to passing gear it bogs and hesitates and shifts hard. if I hit passing gear @ half pedal or less it shifts and runs out perfect. 1 1/2 years ago I did a tune up it has 120,000 mi with a 5.3 L :runaround:

this could be many things...air filter,dirty throttle body,MAF dirty,bad fuel pressures,plug wires,transmission issues, O2 sensors too old,knock sensors defective corroded,engine not maintained over the 120,ooomi,, worn low compression, defective plugged exhaust system...
intake manifold leaks...

Are you showing any check engine type lights on the gauge cluster and have you ran a good engine/transmission code scanner while driving your truck?