Corsa C misfire

[Hornsey]

I'm looking for some advice please about a misfire on my Corsa C 1.2. The car started to fire on three cylinders a while ago so I took it to a local garage I knew had diagnostic equipment. They said that the coil pack had corrosion on it and number 1 cylinder was not firing, so they cleaned it up and all was well again for a while. Then it happened again and quickly became worse - only firing on two now. Number 1 and 4 cylinders are not firing (the plugs are wet when removed). I have now replaced the coil pack with a secondhand unit which has made precisely zero difference. Can anyone advise me where the coil pack gets its signal from? Is it directly from the ecu? I'm just trying to solve the problem myself before I have to take it back to the garage.

[popinoz]

Dunno but if it is the coil pack get it from eurocar parts as i saved a small fortune not going to vauxhall when my missus car broke down with same problem.Im always unsure with second hand bits.