right was on the motorway last night

got off on the slip road

driving home, hit boost and the car started missing/hesitating and making a ppuuuurrrrrpppppp sound

i thought wtf parked up opened bonnet everything seemed ok, carried on going but it was the same


got home took out the plugs, the 3rd plug had its tip missing and was fcuked

so woke up today put in new plugs and leads (to be on safe side)

still same problem, so i thought ive changed everything why not change the fuel filter too, but still same problem

done a compression test, 1,2,4 cyl. are coming up with a reading of 10, but 3rd cylinder is coming with a reading of around 8

anyone know what the problem could be

engine sounds still sweet, absolutely no smoke

all feedback shall be appreciated