I got a 90 1500 silverado 350 4x4. Everytime i start it it idles like it wants to stall for a minute then it runs fine. i put a new cap rotor on it. new plugs and wires. it doesn't matter if its cold or hot it does it every time. and it also only gets 10 mpg when im told i should be getting 15 or 16 mpg. its stock with 225 tires. any ideas.

 

1. IAC
2. Dirty throttle plate
3. dirty air filter
4. Bad battery connection
5. Weak alternator
6. Bad TPS
7. BAd O2 sensor
8. BAd Intake Air Sensor

 

I would change the air cleaner & fuel filter.
Is the check engine light on?