Overheating. 1991 toyota corolla 5spd manual. 4cyl. overheating. oil level and color good. coolant low with oil in it. filled collant with a 50 50 mix, but coolant doesn't flow with engine running. no heat flowing through heater-core with the fan blowing. fan belt ok. engine surges when in neutral. does this mean it may be leaking oil into the coolant through the combustion system? Car normally runs great. from portland oregon

Steam is not smoke. Smoke would be from oil burning, the steam would be overheated coolant which is 50% H2O. Oil making white smoke, more than a little would have a smell that irritates the eyes and nose
while the steam from overheated coolant will smell sweet. The mixing of coolant and oil will be apparent on the oil fill cap when major damage has occurred and looks like coffee with cream.

This is usually a sign of a bad head gasket. coolant is entering the cylinder(s) and is being burnt off as steam. coolant is also mixing with the engine oil. The color of the engine oil would be that of coffee with lots of cream if the head gasket is blown. The radiator would also be low on coolant.

Head Gasket Problem, or cracked head , the heat, then no heat is almost a dead giveaway. Good Luck

You may need to "burp" the system and get the air out. When car has completely cooled, take radiator a off, start car, let it warm up (but not overheat) and see if level drops. Add coolant/water mix to top it off. Never run straight antifreeze. At most a 50/50 mix of distilled water and antifreeze.
Air can get trapped in areas of the system when its been drained. Just monitor that temp and don't risk damaging the engine by overheating.

Its a warning light to let you know that your coolant level is low. When the engine is cold remove the reservoir cap. If the coolant is red add a mixture of 50/50 dexcool and water. If the coolant is green add a 50/50 mix of regular coolant and water. If you cannot tell what color it is add a 50/50 mix of all make/models coolant and water.

Fill until the level reaches the full mark on the bottle.

Sometimes it will take the light a little while to go out and sometimes you literally have to whack the reservoir a couple of times with a rubber mallet to get it to turn off.

If it goes low again in a fairly short period of time than you most likely have a leak in the cooling system.

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its on the side of the gearbox about half way up the case,dont fill past this hole,just let a little oil trickle out and its full

I think that is your temperature light. If it's on, it means your engine is overheating. Do not drive with this light on or you could ruin your engine.

With engine cold, remove radiator cap and check coolant level. If low, add 50/50 mix of coolant & water. Check coolant level in overflow reservoir too. Fill to colde level. run engine, recheck with engine cold.

Well, water or coolant should be added to the plastic overflow tank which will be labeled (usually on a black, round cap) as such. They usually are a yellowish or white plastic which is translucent. You'll identify it by words on the side that say "Full hot" and/or "full cold".

I believe on the early 90s corollas the radiator is a sealed unit, but if not look for an octagon shaped cap that says very clearly not to open when hot. Obviously, this means you'll want to make sure the vehicle has been shut off for at least half an hour or more (depending on how hot it runs.) before removing that cap and checking the level. I would recommend that you not add plain water alone. You should always add at least a 50/50 mix of water and coolant. You can readily find pre-mixed coolant at most auto stores and/or department stores.

As for oil, you will find a round cover, most likely with a gnurled grip, on a valve cover, or in front or behind the engine mounted to a tube about 1" to 1 1/2" in diamater. The cover will likely say "Motor Oil" on the top of it, and may tell you what viscosity of oil to use as well.

First thing i'd do is check & fill coolant as needed, then monitor level for possible leak. Make sure you run the engine when you add coolant, and make sure heater is on. Let it run for quite a while with cap off, to disperse air in system. When coolant level gets low, engine needs all it can get which will cause it to sort of by-pass the heater, until level gets back up where it should be. Low level explains reason for engine heating up as well as no heat inside. Hopefully the reason for the low level isn't anything too bad, or expensive, but you'll know soon enough if you monitor the coolant level faithfully, or if not sure, have your system pressure tested to avoid major problems in future, if nothing major yet.

your carb has a coolant heated choke system if i am correct as car warms up the coolant warms the choke spring. keep full of coolant to keep from other damage