[2000CAYukon]

Tough to diagnose with your description. For example, how is the idle quality? Too low, too high, can you feel a miss, etc.

Things that can cause the problem:

1) IAC - controls idle speed based on PCM commands
2) MAP Sensor - affects fuel delivery based on vacuum
3) Fuel pressure
4) EGR valve and/or solenoid
5) Ignition coil
6) Ignition module
7) TCC Solenoid sticking - locks up torque converter and engine stalls when put into gear

It is easier to diagnose if you know if the problem is ignition or fuel when it won't start.

In general the TBI engines are fairly reliable and easy to work on. The only time my 90 K1500 truck left me stranded was when a MSD ignition coil failed on me.

//2000CAYukon