Originally Posted by juffer
mine was doing exactly the same mine was 15 psi down in 1 cylinder and i turned out to be the piston had broke between the 2 compression ringsand very badly scored the block.hope its not like this in your case
juffer
My rs turbo years a go did precis the same thing, the oil cap keeps flyin off when accelerate the car, the car idles roughly and when i take the pistons off one of the pistons had cracked and the bit fell of when i little bit hit rubber hammer the piston
So i bet there is piston broken.