Q: it's the 1 that runs along the top of the enginge and it has the grey plug from loom, i want to know is can i use the saxo coil pack? does a saxo,xsara, 106 and 206 Ignition Coil Pack fit the 306??

A: Probably, they all use the same parts, it depends on the engine more than what car it is. Most peugeot and citroen parts share the same part numbers so you could check at the dealer. Some times you can have the same coil pack with a different connector (fords often do this) so you can use a different one by changing the plug on the wiring loom