Whats the difference between 1 post and 4 post spark plugs ?
Noticed 2 different types for my car which I won't add here as I've asked so many questions about :)
But wondered which is best, guessing 4 posta s it costs more. Standard bosch ones are 1 post and £2.10 each and the same bosch ones but 4 pole are £3.96
I guess whilst here does anyone know what size spark plug socket is required for the 04 focus 1.8 petrol to remove them. I gather they are under those black patches/coil packs deep down so extension bar maybe needed I guess ?