2004 Mazda 3

Engine Performance problem
2004 Mazda 3 4 cyl Front Wheel Drive Automatic 65000m miles

when I put the gas cap back on after filling the car the engine starts rough until I give it some gas using the pedal then it seems to be ok. I have noticed sometimes at a stop sign or lights it idles a little rough.
August 13, 2010.

Engine running rough or misfiring can be cause by the following: 1. Defective spark plug
2. Inadequate spark/coil, defective spark plug wire.
3. Lack of compression
4. False air leakage.
5. Faulty fuel injectors.
6. Insufficient fuel pressure.
7. Contaminated fuel.
8. EGR valve that is leaking.
9. Oxygen sensors.
10. Throttle position sensor.
11. Idle air control valve.

Aug 13, 2010.