Misfire on 1 and 3 on 1998 Hyundai Accent

I have misfire on my 1998 Hyundai Accent 5 speed I have replaced plugs and coil pack and even had the codes reset and the check engine light still comes on. Now could the car have jumped time which is causing 1 and 3 to misfire I am really stumped on this one. when the car is cold it runs fine give it a little bit and it runs bad, I have put injector cleaner gas boost in and I dont know it is almost like a sensor is bad any Help would work to get this running correctly. Thanks frustrated guy

Asked by for the 1998 Hyundai Accent
It may come down to analyzing the freeze frame data or live sensor data using a professional grade scan tool.A good scan tool allows for non intrusive testing of lots of sensors. 1 and 3 aren't adjacent so it makes you wonder what could be common to both cylinders. Hyundai as a car manufacturer put a lot of free technical information and workshop manuals on line for Hyundai owners. Check out lots of great information.