Overheating (Engines)

Most definitely.

Blockage in the cooling system

No or little fluid in the cooling system

Radiator fan not working

Yes it can. To much oil and the crank can turn it into foam. Which will cause a loss of oil pressure. This can lead to engine damage and over heating if you run it long enough.

There are few reasons why a car overheats. Coolant levels are to be assumed as in the correct levels. If that is the case, you have a flow issue or a heat removal issue. If the pump is running (rarely the issue) then the flow issue could be from your thermostat sticking (a normal failure mode). The second possible issue could be that the radiator itself is plugged and unable to remove the heat. This shows up as a slow steady heating of the system and could take many miles to overheat.

Many things can cause an engine to run hot, make sure that the cooling system is full, that there are no leaks, make sure the cooling fan is operating properly, make sure that the there is nothing blocking air circulation thru the radiator fins, check for corrosion inside the radiator causing blockage and reduced cooling.

Yes, If vehicle overheats it may cause freon (refrigerant) to blow out

no, it will not

Coolant recover tank low or the sending unit on the tank is defective.

If you did the oil change yourself, one way that could happen is if you didn't put any oil back into the crankcase before starting the vehicle. And then it would only overheat once, before the engine would seize up. Also, if you didn't put enough oil in the crank, its possible that there is enough oil to lube the main crank bearings but not enough to make it to the cylinder linings causing too much friction and heat. Not likely. Otherwise the two items are not related to one another, and this could be coincidental. If you had a Jiffy Lube or other service station do the oil change, it is possible that they fouled something up under the hood. I once had a jiffy joint change my oil in Great Lakes, IL. and I ended up with a bunch of cork gasket material in my crankcase causing my oil pump suction strainer to clog up and a subsequent loss of oil pressure to the engine. The main bearings were not damaged due to there being enough oil in the crankcase to splash lube them. Check your coolant level to make sure it is normal. Also check to see of the coolant is clean and free from combustion by-products. To do this, remove the radiator cap, start the engine and look for gasses escaping from the radiator or the coolant bubbling up and over. This would indicate a blown head gasket. Make sure the oil level is normal. If you have an oil pressure indicator, either a gage or a meter or an indicator light, check to see if the pressure is normal. If both the pressure ans level are normal, more than likely the problems aren't related. But like I said, whoever changed the oil could have accidentally broke something (not sure what) under the hood. [To check that your oil pressure indicator light is working, turn the ignition key to the run position (but do not start the car), and all the dash indicator lights should illuminate for a few seconds then go out.]

There are several things to check for overheating. check all belts,,hoses,,and the recovery tank. If the recovery tank is not in good condition,it will not recover antifreeze when engine warms up and transfer it back to the radiator. Next, and the most common problem, is a radiator that is partially blocked internally. Try a good commercial radiator flush,,follow the directions exactly for best results. If it still overheats, have the radiator serviced by a good radiator shop. Make sure you are using a good quality antifreeze/water mix. DO NOT use just water. Antifreeze raises the boiling point of the cooling system,,it is supposed to do that. Remember,,HEAT is the main killer of engines and transmissions. It is worth the money spent on keeping the engine from overheating.

One common cause is when you need antifreeze fluid for your radiator. Often times, the liquid becomes completely used and that is when your engine heats up, which could further result in a cracked radiator.

It can be a significant contributing cause, especially if it's bad enough to keep the system from pressurizing.

more than likely it might be a bad relay,fuse or bad motors on fans, if all checks ok check coolant sensor. to check fans, disconnect fan wires, run a wire from positive to battery,do the same for negative to neg. on battery. if they run they are ok!! a blown head gasket will add water to oil in engine and at the worst, it will leak on outside of engine!!

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Your problem is probably the PCM ($125), not a blown fuse or bad relay. This assumes (as you did not mention it) that the temp indication on the dash is working.

The cooling system is comprised of two fans and three relays. All three relays have power available at all times. The PCM provides grounds to these relays to control fan operation. If the Temp Sensor senses 223 deg f, the PCM applies a ground to the Cooling Fan Relay #1, energizing it and allowing power to be applied to a series circuit for both the left and right fans - power goes through the left fan to the right fan (via the deenergized contacts of the Mode Control Relay) - the ground is after the right fan. Since both fans are loading this circuit, they will both run at a lower speed. When the coolant temp reaches 230 deg F, the PCM provides a ground for the other two relays in the system - the Cooling Fan Relay 2 and the Mode Control Relay. With all three relays energized, a parallel circuit is set up so that each fan has its own path to power and ground, causing both fans to run at a higher speed.

For this to be anything other than a PCM failure would require that you have multiple problems as with any one failure you would still have some sort of fan operation - either single fan in high speed or both fans always in low speed - but not a loss of both fans. No single failure of a relay, fuse or wiring problem will cause this problem!

You can confirm this (if you have access to and know how to use a multimeter) by removing the K14, K15 and K 12 relays. Let your car run and heat up. Once the temp indication goes a bit above the halfway mark on the gauge, check for a ground at pin 85 of the K12 relay socket (top left as looking from the drivers side of the car). The PCM should be sending a ground to energize this relay - I bet you will find it is not. Let the engine heat up to the 3/4 mark on the gauge and look for a ground at K15 socket pin 86 (top left) and K14 socket pin 85 (top left). The PCM should be providing a ground to all three relays now causing both fans to run at high speed.

The PCM does have other logic for controlling the fans with the A/C on, and with the ignition off, but I think the above explanation should help solve your problem. If your temp gauge is not showing the temperature (or always reading on the low side), then replacing it will likely solve this problem as this sensor input is used by the PCM for fan scheduling.

I've had this problem for a while and only started to troubleshoot it today. Been adding coolant/water on a regular basis, but as most of my driving is at highway speeds, the engine normally stays pretty cool (until I hit Northern VA traffic).

I am heading back home from Washington DC to Atlanta tomorrow and plan to install a jumper (bent paper clip) between K15 pin 87 and 87A, which will energize K14 causing the Right Cooling Fan to run on high at all times (I already tested it and it works fine). This should keep the engine temp in the normal range even if I get stuck in traffic. Just remember that if you need to do this to get you home, you will want to remove the jumper if you are stopping for any period of time as the fan will continue to run even with the car turned off. The same result could be had by jumping across K14 pins 30 to 87, but I would not recommend this as this circuit carries the right fan load (not just the load of a small relay) and will get the jumper very hot - maybe even melting it or causing an electrical fire in the engine compartment - not good!!! Hopefully I will get around to installing a new PCM in the not to distant future.

I just had that problem with my 1998 olds, it is either the thermostat, the water pump, or your fans are not working to cool down the engine. narrow it down by starting with the thermostat, then check to see if your cooling fan fuse is not burned out, then go to autozone and they will check your water pump for free. I just had that problem with my 1998 olds, it is either the thermostat, the water pump, or your fans are not working to cool down the engine. narrow it down by starting with the thermostat, then check to see if your cooling fan fuse is not burned out, then go to autozone and they will check your water pump for free.

your a/c unit works your engine harder then not running it. it should not make it over heat, but if it does, check your antifreeze/ water mix in your ratiator, if the level is too low, this may be your problem, if it is fine, check your fan, make sure it is running correctly, you should hear it come on when your engine is getting hot. if this is also working fine, heck your radiator and make sure the fins on it arent bent in any way, a few bends are ok, but if 1/4 or more of it are bent, get a different radiator, lastly, check and make sure you dont have bugs clogging your radiator (this has happened to me)

No it should not check ur antifreeze and make sure its up to level.

it may be because the aircon swithch is on.

or someone shorted it to work as a prevention to engine overheating.

when the enjine was turnoff sometime and then open the radiator and fill it

Too little coolant, or a plugged coolant line.

The wrong thermostat has been installed, perhaps a winter thermostat for a cold climate when you live in a warm climate. Or maybe the coolant level is low due to a leak. Two possibilities anyway.

Make sure you are using the correct thermostat for that vehicle and that it is opening and closing properly((sometimes even a new thermostat can be a bad one)) also check coolant levels,make sure you are using engine coolant in the system and not just plain water only......a minimum mixture of 50% anitfreeze/coolant and 50% water is normal..you can even by the pre-mixed engine coolant from autoparts store..

If your thermostat is operating properly and you have installed a new radiator then the next option is to have the vehicles coolant(water)pump checked to insure it is operating properly...also have the vehicles temperature sensor check to insure it is operating properly...

Also since you replaced the thermostat and the radiator you drained the entire system and now you may have air trapped in the system,when the coolant system is filled at the factory and at most garages/dealerships they pull a vacuum on the system until the radiator hoses collapse and then fill the system with engine coolant...this prevents air being in the system which can cause cooling problems as well...

I want to add there is a specific way to install a thermostat. It has to be placed in the certain position inside of the inlet. There is a special marking to assist you.

Replace sending unit

that's because car was on too long.

that's because car was on too long.

try checking your cooloing fan. make sure it is running

There is no air getting to your radiator as you are not moving! Or there is a problem elsewhere in your cooling system!

A number of things. The fan relay or temperature switch may be bad (electrical fans), the fan clutch may be worn out (older vehicles), the radiator could be clogged internally, too much debris in front of radiator (air can't get through to cool collant), blown head gasket, or a cracked head. Also the thermostat could have been installed backwards.

I had a 2000 Taurus with the same problem.It was the blower door motor.Its the little motor that opens and closes the door that directs the heat to the vents.Cost me $330.00 at a dealer because the average person can't get at the motor.Hope this helps.Also have the thermostat looked at,it could be stuck open.