2000 hyundai elantra w/ engine troubles. how can you tell if it's the injecter or the coil?

Question

we just got this car from a friend, and one of the pistons isn't firing. we replaced all the wiring and the spark plugs. we believe it's either the fuel injector or the coil but can't figure out which one it is. help?

Answer 1

you have a coil for each plug then you have a bad one or a injector... pull a wire and crank it over and see if that one wire is firing or not easy.. could be more like a bad cam lobe or valve