1996 Mitsubishi 2.8
I was going 75 mph in 5th gear when I heard a weird noise, followed by a loud exhaust bang and a lot of smoke all at once (I saw it in the car’s mirrors). Then the speed started to drop, even though I still had my foot on the gas. The temperature needle shot up to the maximum. I pulled over and, as you can see in the video, I couldn't add water even after the car had cooled down. https://youtube.com/shorts/5uRZ7ktMr8s?feature=share
I'd say that after 30 years your engine has given up the ghost. At a minimum you have a blown head gasket, or cracked cylinder head or block. Time to shop for another car.
@chucktobias I just got this car 😅 life is funny
I just got this car
That's the chance you take when buying a car that old. Sometimes it works out but it's a real gamble. It is quite possible the engine already had a head gasket leak when you bought it that the seller temporarily masked with some snake-oil "sealer" goop that finally let loose.
If you're able to do the work yourself the repairs might be feasible but it would cost more than the car is worth to take it to a mechanic.
@chucktobias I'm from outside the US so this car worth between $10k - $13k plus the paper and the frame alone worth like up to $5k,, the only option for me is to try and fix it so what to start with to diagnose the problem?
Verify exhaust gases getting into the coolant using a test kit. (Though it's pretty obvious from your video that's the case as well as oil+coolant mixing.) Assuming that's the case tear down the engine to find the cause, which could be a head gasket or cracked cylinder head or block.. If coolant has been getting into the oil you may also have main, rod, and/or cam bearing damage so you would need to check for that as well.
Installing a good used engine if you can find one may be the best option.