I am working on soon to be son in-law's Neon and it is giving me a hard time. I went to investigate a no start situation and it cranked like it had no compression. I took compression check and confirmed 60, 70, 0 and 30 psi. I assumed timing belt broke or slipped because car was running fine the day before. Got it in the shop and inspected the TB, nice and tight, timing marks lined up and no missing teeth. Next, put compressed air to cylinders (with valves closed) and can feel air flow at tail pipe on all cylinders. I don't know why one day it went from running to no compression on all cylinders. I pulled the head and no smoking gun here either. Gasket looked good and no valves stuck open. Tomorrow I'll take it to the machine shop to have the valves, guides and seats inspected. Any ideas out there? thanks in advance.

 

I pulled the cylinder head and dropped it off at the machine shop. Exhaust valve guides were worn and this allowed carbon to get up the valve guide and cause the exhaust valves to stick in the open position. Thus no compression in all cylinders. I ran across others who complained about bad valve guides during my research. Engine back together and problem solved. Valve grind with new exhaust guides and resurface for $180.00. Car runs good.