Pontiac Repair: #1 Cylinder Missfire, obd2 code reader, chevron techron

Question
i have a 96 Pontiac Grand am,2.4L 4cyl. twin cam fuel injected,2door 4sp manual trans.
my engine check light came on so i Pluged in my "OBD2" Code Reader and it gave me a code of: P0301 (Cylinder 1 Misfire Detected) i then did some checks as described in manual: used a long screwdriver to hear if #1 injector was clicking when running.Yes it was it was  steady not intermitent. then i used a ohm meter to check the resistance of #1 injector,which was with-in spec range shown in manual. no other code was shown on the reader.the car is running rough at idle. when i get off freeway and come to a stop it stumbles as if it was missing on 2 cylinders then catches back up  as if #1 cylinder is slightly missing on that cylinder. so is there  any possibility that #1 injector is clicking as it is working but some stuff is on injector causing it to react like that??? ive used that "STP Carb & Injector Treatment" stuff in 4 -5 tankfulls now and not clearing up. any sugjestions

Answer
Hey Wally:

Those code readers are okay but a scan tool is what you need so you can acytually see the misfires occuring on which cylinders. On that car the coils are pair up. each coil fires 2 plugs at a time. 1&4 and 2&3 paired up together. It is possible to have a plug cracked or one of the boots between the poil housing at the plug being bad and arching. it coild be a bad coil nat that's why at toke you feel it more like 2 cylinders are not fireing. That additive in the tank doesn't work to well. One that does is Chevron Techron. That works well. My guess is this is an ignition issue and not a fule injector issue. Good luck :}