Hyundai Accent 1.5L LC from 2000 misfires
I have a Hyundai Accent 1.5L 12v from 2000, and lately it has been misfiring a lot. I have read out the error codes, and it indicates a misfire on cylinder #3.
Then I tested the spark plugs and spark plug wires, and I found that the spark plugs were fine, which I expected because I changed them about 10,000 km. ago. I have replaced the spark plug wires, and I have tested them with a device that blinks when a spark is made in the cylinder. And I found that cylinder #3 and #4 weren't sparking at a uniform way, sometimes they would stop sparking for 3-4 seconds. Then I replaced the coil packs, but it's misfiring, and I'm running out of ideas.
I hope You maybe have some ideas for what could be wrong!
Sorry any bad spelling, I'm from Denmark, so English is not my best! BTW the car have clocked 230000 km.