Cruising the motorway at 70 and suddenly the engine starts popping. Clearly on 3 cylinders. Call the AA and it seems the spark plug far right has come out. Closer inspection the gap on the tip has gone so looks like the piston has come up and struck the spark plug? It's pretty much stripped out the thread and of course if the piston came up that high does it mean my engine is ruined? Please help! Thanks
Car is a 53 Clio 172
Car is a 53 Clio 172