Ka misfire, or something, my baby is running tough.HELP!

[sr20deTsomeday118]

ok guys, i was driving yesterday and then as i pulled up to a stop light my car starts to shake and it feels like the engine is mis-firing in a cylinder. anyways. i checked plugs, all ok. i bought a spark plug tester to check to see if each individual wire was sparking. they are. i pulled apart the distributor thinking maybe the rotor itself was maybe bad. it was fine. im stumped. any other reason my car would do this. ill post a vid momentarily.

[Razi]

Idle air control valve might be fouled up.

[dirtyfingers2]

check your maf..clean it, iacv like razi said. pcv..are you using good gas?

[sr20deTsomeday118]

it was an injector prob, i replaced number 2 cylinder injector and bam! all good. def thanks for the responses guys. NICO FTMFW!