Travelling on the M25 at 9am lots of traffic, sudden and increasing knocking noise.
Indicated, changed lane and decreased speed but within seconds there was a bang and the engine light came on.
Engine stopped, but luckly managed to pull onto the hard shoulder.
Car was covered in oil around the sides and bumper.
AA towed car to garage.
Timing Chain Tensioner had failed so they carried out a compression test to check damage, which showed a failure on 1 of the cylinders.
Thinking this could be fixed they removed the exhaust manifold and found that the bottom end w