Hyundai i10 2010 code 303 misfire cylinder 3

Question

checked plug and lead swooped coil pack over but also some times hear a buzzing from fuse box now and then and it last only a second or so

Answer 1

HI there,

I would next swap the fuel injector with the one next to it, if the misfire moves then replace the injector,if not then I would do a compression check or a leak down check on #3 to see if there is low compression. You may also have a small head gasket leak.If you have coolant leaking into the cylinder it will prevent combustion.