HI all, I'm new here, but have been lurking these forums for some time gathering useful information. Members here seem very knowledgeable and would appreciate some advice.

2003 Sunfire L61 2.2 ecotec. Cranks great but no start. No CEL or SES. Heres what I have done so far.

Checked spark, Good spark on all 4 plugs.

Rented fuel pressure tester, but fitting didn't fit securely on the valve, couldn't get a reading. However I did press the valve open manually while turning on the pump and fuel sprays out very strongly. I did spray starting fluid directly into throttle body and got nothing, No sputter or any signs of starting, so I have more or less excluded fuel delivery issues from possible causes.

My compression tester showed 0 PSI on all 4 cylinders, However I think my tester is bad. I blew through the hose (which inserts into spark plug socket) and could not get ANY air to pass through the hose. I will get a new one tomorrow and report back.

I did do leak down tests, but I have a very cheap ($40) unit, and I question the accuracy. Tests were done properly at 15(ish) psi. All tests were in the yellow area (moderate)
Cyl 1 - 30-40%
Cyl 2 - 40%
Cyl 3 - 50%
Cyl 4 - 55%

Upon removing the valve cover, there was slack on the timing chain. A good amount causing it to sag quite a bit. I suspect the timing may be off, which could cause bent valves.

Other notes:

With the valve cover off and spark plugs out, There was very little air coming out of the plug hole. During the compression stroke there should be alot of air coming out of that plug hole. I could barely feel any air with my fingers. I also put duct tape over the holes, and while cranking the engine it didn't even blow off the tape, so there's seemingly no compression.

I could remove some of the rocker arms by hand, as well as replace them by hand. The last L61 I worked on the rockers stayed firmly in place at all times.

Any suggestion or advice is greatly appreciated, sorry for the long read but I wanted to be informative as possible.

Thanks in advance!