Lumina z34 Coolant boiling/bubbling

Hey! I just bought this 92' lumina z34 and I was driving the other day and saw smoke coming from under my hood, so I popped it and looked at my coolant and saw it boiling/bubbling and I have a crack in the top of the resivoir so it was spewing everywhere. I even drove it and it spewed so bad I had a puddle under my car and there is no leak any where in my car (I checked before it happened). Can you help me out!? Also can you just clean an egr valve and it would work better or should I replace it? Thank you.

try flushing your radiator and putting an exact 50/50 mix back in.
and yes you can clean an egr valve. purchase the gasket then use deep creep to clean out the valve, the manifold, and the egr pipe. it will smoke like hell after cleaning but will go away in about 5 mins. you can also use an egr bypass "i used sheet metal" to help keep the manifold clean. ofcourse if you use a bypass, you have to tune the computer so the ses light wont turn on. I bought a performance chip which had that feature "wot-tech.com". $99 for the 92 z34 chip...

Hey thanks. but do you think it could also be a thermostat problem?

always put a new stat in when you flush. its a cheap part...

thanks for the help