Why does my car keep running too hot?

firstly you don't know what temperature your car is running at if you only have a temp gauge that goes from cold to hot. The two cars could be running at the same temp but the gauge doesn't tell you that.

It is normal to run hotter while slow driving around town as not as much air is flowing through the radiator to cool it.

Don't remove the thermostat because it is designed to hold the water in the motor while the radiator cools the water in it, then the thermostat opens allows cooler water in, closes the thermostat and allows the radiator to cool the next lot. Without a thermostat it will just keep flowing through and eep getting hotter and hotter as the radiator hasn't got a chance to cool the water properly.

It is possible someone has already taken out the thermostat causing that to happen.

But without a temp gauge that shows you what temp the motor is REALLY running at you don't know if you even have a problem.

Also check the level of transmission fluid, if that is low it will run hot and because it runs through a tank inside the radiator to cool, it will warm the water before it gets to the engine.

Heaps of possibilities

When there's no road wind cooling the radiator and engine, then you have to depend on your radiator fan to cool the radiator. Open your hood and make sure the radiator fan is coming on when your overheating. If not, you could try installing a new fan thermostat and fan relay. Look up the parts on http://www.autozone.com/ for your make year model and click on troubleshooting the coolant system and installation of the parts. Of course you must remove your radiator cap (if it has separate cap in addition to the coolant reservoir cap) when the engine's cold to make sure the radiator itself is completely full of coolant. If it isn't, top off the coolant and replace the radiator cap with a new one.

The answers above provide good information as well. One final note is to never let the engine suffer severe overheating for very long because that can lead to expensive engine damage and repairs. Always carry a couple of gallon water jugs with you to refill the radiator after you allow the engine to cool.

On cars there are Fan thermostats. While you are driving , enough air passes through your radiator to keep the coolant at a safe operating temperature.when you stop, the fan thermostat, senses that the coolant is too hot, and turns on the fan's at the radiator older vehicles had a mechanical fan and ran constantly.see below

http://www.partsgeek.com/catalog/1998/chrysler/seb...

http://wiki.answers.com/Q/What_is_a_thermo_switch

it could desire burped. that's the situation: the motor vehicle is finished of coolant and the reservoir if finished. After working the motor vehicle for a jiffy it overheats then cools as quickly as close down basically to do it oftentimes. Boiling over the reservoir if opened. The coolant is replaced and it happens lower back. i'm annoyed! do not difficulty that's an incredibly basic challenge with an uncomplicated fix. that's the concern: The engine coolant became at sometime in the previous low adequate to permit an air pocket in at the back of the thermostat. often engine artwork became executed that allowed the coolant point to drop and this challenge resulted. All thermostats have a tiny hollow or notch cut back in them to ward off this yet by fact of degrading gaskets, loose silicone blue goo, and contaminates those vents grow to be blocked. This traps the air pocket at the back of the thermostat. Your vehicle now needs “burped”. i'm not attempting to be humorous, it incredibly is the technical term for it. that's what's going on: The air bubble at the back of the thermostat keeps warm coolant from coming in touch with the thermostat. with out coolant touching the thermostat it won't open. If it did the device might burp itself and the concern might end. So, the thermostat keeps to be closed and the coolant boils over getting into the radiator backwards, cools and the cycle starts off lower back. in case you have been to open the radiator cap it would shoot coolant out like a shotgun then take a seat and percolate like a coffee pot. a thank you to repair it: you could burp your vehicle by applying looking the optimal element in the coolant device at the back of the thermostat. On American V8 vehicles that's merely approximately constantly the heater hose. As for imports you will ought to apply your ultimate judgment besides the undeniable fact that it is going to possibly be the heater hose or carburetor heater. some gasoline injected vehicles use manifold warmth too. besides, discover the optimal element and vent it by applying removing one end, the optimal one. Now, if executed wisely the coolant device will now settle for extra coolant, often a minimum of yet another gallon. it incredibly is the way you will understand if it became the concern, by applying all the extra coolant you could now feed the device. save including till if flows out your vent. replace the vent and perfect off the coolant lower back. Your challenge ought to be long previous.

You may be low on coolant. Your radiator may be plugged internally, or have a lot of dirt and fluff on it externally. It is not likely to be your thermostat, but it wouldn't hurt to put a new one in at this point. Also, your cooling fan may not be coming on like it's supposed to.

1. The thermostat is faulty

2. Needs a fan belt

3. has a radiator leak