[longknocker1]

I have a 1997 legacy outback with the 2.5L engine with bubbles in the radiator. I was trying to find the leaking cylinder by taking the spark plugs out 1-by-1 (hoping only 1 cylinder was leaking). Here is my question: Why does the engine sound like I poked a hole in the exhaust when the spark is out???? Is my timing belt a notch or 2 off????? With no compression it should be quite not super loud.

Thank you in advance for any ideas.

 

[canubaru]

well, you are forcing 180 psi through a 1/2 inch hole every time the engine rotates. i think that could be kind of loud.

but why bother, it is not recommended to replace only one head gasket.