Oil is milky, ran hot, gauges went crazy, no heat being blown

it sounds like your thermostat is stuck shut..and the antifreeze is getting blown out during operating as you drive it..when replacing this thermostat I have a trick for you to do with it..since the thermostat is basically a mechanical open/close valve..sometimes it screws up and sticks shut..this causes the antifreeze to overheat in the head and blow out of the top tank/hose area on the car(there is an overflow hose there)on the radiator..now when you go to install the new thermostat.. try drilling 2 small holes at a 90* to the bridge over the actual spring-loaded valve.. these go into the wide flange that surrounds the sides of the thermostat, as close to the center as you can go without going thru the center.. these will be called weepholes..IF there are any hairline cracks in the head(s) these weepholes will allow the air to go thru without dropping the antifreeze levels in the heads..the pressure will bleed off out of the radiator cap.. and your heater will still stay warm..

sounds like water pump is broken

If temp. Gauge goes way up check the intake gasket may be blown out and leaking. Take a flash light and shine it under throttle body and look for coolant. Check radiator to make sure it is full only check radiator when engine is cold DON'T OPEN WHEN HOT can cause burns.

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These details will help.
Thanks.

Check for blown head gasket if there is steam coming from the exhaust,also check that the theremostat is opening.

No, because it blows cold air when it gets hot. There is air in the system or the coolant is low. Intake manifold gaskets are a very common problem on these engines and if left unattended to can cause even bigger problems such as head gaskets if the engine over heats too much. Check the coolant level and if it is low, look for leaks at the water pump, radiator and especially the intake manifold where it meets the head. Also, pull the oil dip stick an/or the oil cap to see if it looks milky. If it does, there is coolant getting into the oil.

head gasket for sure or the cylinder liner, whats your oil look like? milky? if so you got a severe problem, I would pressure test the cooling system and leave pressurized for a time and watch oil level as its pressurized

No heat is often a symptom of low coolant, usually followed by overheat. There are other controls that regulate heater, but right now, re-fill the cooling system with engine running and heater on high, then check for leaks (coolant you lost went somewhere...you need to determine where) Low coolant will damage your engine. Take care of that first, then if heater still does not work, then do diagnosis on that. (if you loose the engine heat won't matter, will it!)

It sounds to me like you're low on coolant. When you checked the coolant level, did you actually open the radiator cap and make sure the radiator is full? The plastic tank you generally add coolant too is actually an 'overflow' or 'reserve' tank. There is a hose that runs from that tank to the top of the radiator so if the radiator gets low on coolant, more coolant -should- run in from the overflow tank. However in practice this does not always work. I have a Jeep that leaks coolant and experiences this exact same problem. Coolant will not run from the reserve tank into the radiator because the hose is plugged up, and whenever the radiator gets low on coolant the temp gauge will go real high and then drop, and the heater doesn't work well. This is because the cooling system of your car is supposed to be a closed system, full of coolant and no air. When coolant leaks out, the space it used to occupy is now occupied by air, which does not transfer heat well. When 'air' is passing through your cooling system, no heat can be transferred from your engine to the heater and radiator, resulting in a hot engine and no heat at the heater. Then when a pocket of water passes through the system, the temperature gauge quickly falls as the water absorbs the heat from the engine. The hot water that cools the engine is where the heater gets it's heat from as well, so when water passes through the heater core, the heater works, but when it's filled with air, it doesn't.

First when vehicle is cold like in the morning check and make sure that the vehicle has enough coolant/ antifreeze in radiator and reservoir. If coolant is need use a 50/50 mixture of water and antifreeze. You will need some time to do this let car run at idle until the temp guage is in the middle NOT+ normal operating temperature. At this point if the thermostat should be in the open position. Let vehicle run and check to make sure that radiator fan comes on. This should come on when guage is about midway/half way. If temperature rises above half going to h/hot and fan doesn't come on, you either have a BAD FAN BAD FAN SWITCH BAD FAN RELAY OR BLOWN FAN SWITCH FUSE. You will need to check all of the following I will help if its needed. If fan comes on and doesn't go off and vehicle continues to get hot even with fan running. Feel radiator hoses and see if the lower radiator hose is cool/cold. If it is you have thermostat that stuck closed. Replace thermostat and fix problem. If all the above is good and vehicle continues to over heat. THE BAD NEW IS THAT YOU MAY HAVE A BLOWN HEAD GASKET /CRACKED HEAD /BROKEN WATER JACKET. Basically you will need a HEAD JOB at least a head gasket. ONe tell tail sign of this is oil looking like milkshake/chocolate milk-a creamish while residue in oil or antifreeze. Contact if you need hel0p. Good Luck and thanks for using FIX YA