A few weeks back when pulling out at a roundabout I had a sudden loss of power and the car started juddering. Took it in to a local independent Ford specialist who did a compression test and found that the compression in cylinder 3 was around half of what it should be. I was told the car needs a new engine (it's only 10 months out of warranty and has just 24k miles on the clock).

I removed the coil pack and spark plug from the affected cylinder and put an endoscope down there and found some pretty bad scoring on the bore. Is this likely the result of a failed piston ring, broken valve or something else? What could have caused this?

I've been in touch with Ford who have been absolutely no help whatsoever during the 3 weeks I've been in contact with them. They want me to pay ~£1,000 to have the engine stripped to determine the cause, and would then "evaluate the costings" if the fault was deemed to be a manufacturing defect and not wear and tear (I argued that it can't be wear and tear on a car with such low mileage which has been properly maintained). I've had a basic diag done at Ford dealership who confirmed loss of compression, but the car apparently passed all of the tests related to coolant issues.

Any ideas?

Edited by terrytincan on 29/08/2019 at 17:53