Coil has a high voltage leak

Hello friends, I have a problem that I want to solve, after a time belt change, take out the workshop vehicle a 2002 Hyundai Accent and worked well as three days later I started pulling, corcusing, I do not know what to call it, the detail is that I feel it with lack of strength but at the same time pull as if the spark plugs did not work well ... In view of that I check, I changed the spark plugs and Accelerate it jumps a spark from the coil to the motor mass of a specific cable. Change for new cables but the spark continues to come out at the same point ... I do not know if it is due to the same but I have noticed that more white smoke says goodbye for the escape something that before changing a belt of time and the fault mentions the mention does not do it ...

please any connoisseur can clarify the subject?

Well, I tell you. Finish changing the ignition coil and the disappearance failure.