The 'hissing' sound when the engine dies is likely the normal stabilizing of vacuum in the cylinders as the engine stops turning. I have multiple fully functioning 1zz-fe & 2zz-ge engines which all make a faint hiss when they are shut down because the crankshaft continues to turn for a half second after the ignition is cut and that generates compression in the cylinders, which 'hisses' as it escapes the cylinder into the intake or exhaust manifold of the stopped engine.
I don't think vacuum is your problem, it's more likely electrical. There are two eyelet ground straps which attach to the 'lift' solenoid with a couple 10mm nuts. Make sure these are clean and secure b/c I can tell you from experience that if they aren't attached the 2zz will do exactly what you described. Ask me how I know.
Best to check for CELs first it may indicate where there is a connection problem. Then go back over your work and use zip-ties to hold broken connectors together. If all of that checks out my guess is occam's razor: the solenoid you replaced your old one with is defective and needs replacement.
I don't think vacuum is your problem, it's more likely electrical. There are two eyelet ground straps which attach to the 'lift' solenoid with a couple 10mm nuts. Make sure these are clean and secure b/c I can tell you from experience that if they aren't attached the 2zz will do exactly what you described. Ask me how I know.
Best to check for CELs first it may indicate where there is a connection problem. Then go back over your work and use zip-ties to hold broken connectors together. If all of that checks out my guess is occam's razor: the solenoid you replaced your old one with is defective and needs replacement.
