A BIG Problem

Ok so I thought my motor was blown but it fires up great and drives good but coolant is still going away. Someone told me that the catylatic converter can clog and force coolant up and out the exhaust is this true on the 1995 blazer w series engines? I just did the intake gaskets and it ran grea then started overheating and pouring smoke and the only code its throwing is the O2 sensor. What am I to do????

Sorry, a clogged catalytic converter can't cause coolant to come out your exhaust but a cracked head/block, leaky intake gasket or head gasket can.
See if there's water in your oil.

No water in oil. I did a pressure test all around 180 psi just changed the spider injector and redid the intake gaskets it makes no sense I am running the uv dye test on it now. who knows what itll be

UV dye test revealed nothing. Tomorrow ill pull the plugs again and start all over. Is there a scanner I can get that will tell me whats wrong without a check engine light.

This doesn't sound like a control issue, and a scanner probably won't do much good with a mechanical problem.

If the pressure test reveals nothing, and a UV tests shows no trails, yet you're still losing coolant, you might want to look at the transmission oil as well as the engine oil, the heater core, and any other external leaks.

No scan tool will find that problem! Pressure test the cooling system up to about 15psi and watch for a leak with the black light. The dye you put in will show up flouresent green where it leaks out. If there are no visible external leaks and the pressure drops, check the intake gasket and as Blue Bowtie mentioned, the transmission oil.

Ok now there is a sound of water sloshing in my heater core and i tried the air bubble thing But it came right back any suggestions?

oh yes and I lost all my heat after driving it around today but it never overheated just blew cold air

Water sloshing and no heat are both signs of low coolant.

Yes and I never even thought about the transmission Ill check it now

tranny oil looks perfect still nice and red

how do i pressurize the system i tried running it but nothing appeared

Need to use a cooling system pressure tester. Remove the radiator cap, install the tester and pressurize the system to about 15psi, then watch for leaks.

was intake gaskets sorry for waiting so long to reply