Zero compression after one month of being garaged!
 

I went overseas for vacation and left my car in the garage. When i came back the battery was dead and jump start it. it would crank but no start. I know i had really worn plugs before i left so i replaced them and gave it a start. It started up smoothly up to 3000 rpm and died smoothly. No clunking noise, no banging, no sound of anything being blown. I had fuel, spark but no compression. I did compression test and weird thing is all 4 cylinders has ZERO compression. I asked older techs and had to advice of adding little oil to cylinder and test again. still ZERO compression. I took the valve cover off and nothing was damaged. Checked timing and the timing belt felt slightly loose. Replaced the belt and tensioner. Got everything timed and tested again. Still ZERO compression all 4 cylinder... i feel air coming from the cylinders really noticeably but gauge shows no compression. I went out bought a new gauge to make sure my old gauge wasn't broken, Same thing... now i am fairly lost on why am i getting no compression. Injector seal is good, head gasket doesn't seem to be blown. When i did leak down test at TDC. It was showing 30% leakage average all 4 cylinders... any advice?

When you did a leakage test where was the air going?

Make sure the o-ring is making a good seal. Sometimes dirt gets in there and the tester reads faulty. How many miles are on it? Possible the compression rings are froze up in the pistons.

how are you doing your compression test? i have never seen a cylinder with 0psi compression on the gauge compress a mixture enough to combust and run an engine.

Rings, head gasket, Warpage, Sparkplug Thread Stripped. and of course Your valves hopefully are able to fully seat.