If your car has cooling fans, make sure they are working correctly. Make sure the radiator isn't leaking and not restricted either on the inside or in front on the outside. Caution: Always disconnect the negative battery cable before putting you hands into a vehicles engine compartment. Caution: When the engine is hot be very careful not to touch hot engine parts. If your not sure what your doing get help from a pro. First when the engine is cold check the radiator and make sure it is topped off with coolant. Reply: This could be caused from a number of reasons and it is helpful to give more information about the car like make model and year. Let me explain there are at least two ways of cooling the radiator. Some cars have an electric fan that is controlled by a thermostatic switch normally located near the bottom of the rad when the car gets to a certain temp the fan will come on and cool the radiator and when cool shut off. Other cars have a fan driven by a belt from the engine in the center of this fan there is a thermostatically controlled clutch which detects the air being drawn thru the rad when the air is to hot the clutch will cause the fan to turn more drawing more cool air thru the rad. When the air coming thru the rad is cool enough the clutch will allow the fan to slip or free wheel. If either type of thermostatically controlled switch goes bad the car will overheat at idle. The car cools down while driving because the cool air is forced thru the rad. Please do not confuse this thermostatic switch with the heater/engines thermostat. I personally would check or take the car to someone qualified to check for a bad electrically controlled thermostatic type of switch on cars with electric cooling fans. On cars that are driven by a belt I would check the fan belt for slippage and the fan clutch it self when engine is cold for oil leakage or when rocked for excessive bearing play and spin the fan by hand to make sure it turns freely then start the engine and allow it to run until the heater is putting out hot air next turn the engine off and spin the fan again the fan should be harder to turn as if there is a drag on it if not I would replace the fan clutch. Electrically operated fans: Parts to check fuses, electric fan motor or thermostatic switch, or an electrical problem. Fan Belt Driven fans: bad broken or slipping belts, thermostatically controlled fan clutch, and cracked or broken fan blades. Check both type systems for a blockage in the radiator core such as bugs dirt leaves. Last but not least if the core if self is clogged internally you might need to flush the system and or have the system pressure checked including the cap. PS Many people on accident put the heater/engine thermostat in backwards this will cause many problems This thermostat is like a one way valve and must be installed in the correct direction.
A lack of water in your cooling system will cause your 2002 Pontiac Sunfire to overheat. A malfunctioning thermostat can also cause it to overheat.
Stuck thermostat, clogged radiator.
When a thermostat goes bad in a vehicle, it can make your car overheat. It can also make it t where you do not have any heat inside your car.
Yes it can cause it to overheat but first check your thermostat. That would be the 1st cheapist thing to do before you did anything else. I got an 85 regal(overheating) and the thermostat or the heater core is the problem im getting them both replaced tomorrow and will let know of how it runs.
I have the same problem and I think that I have found out that the radiator is too small for the size of the truck.
Did you make sure that you are putting the themostat in correctly? If you put it in backwardthis can sometimes cause this problem.
sounds like you need a good flush,of system.and change anti-freeze! check and make sure water pump is circulating coolant!! first.
The antifreeze level could be low, or the thermostat may need to be replaced, or the antifreeze line might need to be blead to get all the air out, the air in the line will make it overheat.
just because the thermostat is new doesnt make it good your supposed to boil it in water to see if it opens and closes so it may be bad. if your car is low on oil it will overheat also or start the car and watch the radiator hose it it collapses then the hose is clogged and the water isn't flowing right which will cause it to overheat.
Try changing the themometer
low coolant level check for leak and repair add new coolant and burp the system to get all the air out and make sure thermostat is working properly
The thermostat will need replacing. It us either stuck open or closed. When you open hood, there is a hose that goes from rad to engine (top not bottom). Thermostat sits where it attaches to engine. $10-15. Make sure to clean old gasket off and replace that as well. You should be good another 4-6 years
look at you thermostat sticking that happened to me in my 79 chev or check for plugs in rad
The thermistat could be bad, check to make sure the fan is kicking on.
Low coolant? Plugged or restricted radiator? water pump not circulating coolant? Thermostat not opening fully? Defective radiator cap? Hoses collapsing under pressure?
Does the computer also say low coolant. On start-up mine did that so I'm pretty sure it does that to make sure you check that the coolant level is ok. If coolant level is good then the thermostat is probably stuck open.
The plastic intake manifold on these cars often cracks near the thermostat housing as well. Also check the front of the intake manifold just behind the alternator for leaks. See more info here... http://www.autoclinix.com/Manifold.htm If the thermostat is stuck closed, it is possible that the water would back up and leak through the thermostat gasket. however, it would also make your engine overheat. If your engine is not overheating, then the leak is probably coming through a crack in the hose where it clamps to the thermostat housing.
A stuck closed thermostat would make the coolant temperature symbol illuminate.
If you're stuck in traffic and your water is low, even a little, it will overheat... or your thermostat is not opening all the way. Or your fan is not kicking in at temperature. Make sure your antifreeze is properly mixed, beause it is a coolant, too.
my guess is the thermostat if you just replaced the thermostat then it might be an air pocket in the cooling system solved by taking the cap off the overflow tank squeezing the radiator hose going to the thermostat housing until the water pressure opens the hose in your hand this forces your thermostat open. if you decide to replace the thermostat yourself do the same as above to make sure all air is out of your cooling system.
Check to see if the thermostat got put in backwards. Make absolutely sure it's completely full of coolant.
low coolant levels
It probley has an AIR pocket in the cooling system. Bleed the air out of the system and make sure it is full of fluid.