I've had a Mazda 323f for a few years now with no faults. But now, it's running poorly with a loss of power that then picks up.
I replaced the coil pack and it ran great for a few weeks but then loss of power again.
I swapped: plugs, leads, fuel pump. Still no joy and getting ready to get rid of it.
Someone told me that it was too much air getting in. But you do get a smell fuel so I thought the coil-pack may have gone again but sounds alright when engine is not under pressure.