my car is overheating but when i turn on the air the car its fine what is wrong with it..?

Question

well i bought a car and i noticed that the thermostat rises showing that the car is over heating but when i turn on the air, the thermostat goes back to normal and if i turn it off the car heats up,,,,,whats wrong with it and can I fix it and if so how much...also how much would it be to get a full service tune up on a 2000 pontiac gt grand am

Answer 1

Could be a stuck thermostat if your lucky!

Here is a list of the most common things it could be http://autos.yahoo.com/maintain/repairqa/fluids_heat_air_conditioning_general/ques014_2.html;_ylc=X3oDMTBybXF0cjE1BF9TAzk3MjY0NTAyBHNlYwNzbXgEc2xrA3NteA--?refsrc=offnetwork%2Fcpc%2FPI

Good luck!

Tune up would be cheaper to do it yourself! ;-)

Answer 2

it sounds like U have a problem with the raditor, thermostat, or the fans.

the air in the car is heated by the engine water, so turning it one acts as a cooling fan

here what U need to do

U want to check the thermostat is working properly, it is housed in a small chamber, with a large hose coming out of it to the top of the radiator, take it out, and look around the edge of it, U r looking for its operating temperature, it will be stamped around the edge.

find that temp, and put it in some water at the same temp as that, U should see it open, if it doesn't replace it, U must remember to renew the gasket when replacing it

next U want to check the fan works, there should be a temperature sensor for it, on the engine some where, disconnect it and put a wire into the socket leading to the fan, this will bypass the sensor, with the key in the ignition and turn to position 2, the fan should run, if it doesn't, the fans faulty, if it does the sensor maybe faulty.

check that the water pump turns freely, and stiffness, and it needs replacing.

to check the sensor, run the engine up to temp and wait the fan should kick in, if it doesn't and U checked the fan works U need a new sensor

hope this helps

Answer 3

late model cars have a thermostat that tells the radiator fan to come on . the power for the fan goes thru a fan relay.the fans are operated electrically.

some automobiles fans also come on automatically when the air conditioning is turned on.

check and see if your fan isnt coming on when you cut the ac on, even when the radiator is cool.

if it is, then you have a bad fan relay or bad thermostat.

go to autozone. ask them to find these two items on your car for you, and if you can buy them , replace both of them.

they may even help you do it. the relay plugs in
but you will need a wrench for the thermostat.

if you just bought the car, you might want to replace the radiator thermostat. some old heads will remove the thermostat like you used to be able to do with cars whose fans operated all the time mechanically. if this has been done to your car, the temperature will be eratic and nothing except installing a radiator thermostat will solve it.

radiator thermostat--$11 ( aprox)

heat indicator thermostat--$ 6 ( aprox)

fan relay--$ 30 ( aprox )

Answer 4

First, check the RADIATOR for rusted-out ruffles, and leaks. A radiator costs in range of $89-$125 depending on where you get it serviced. Always go to a "reputable" place to do that kind of job, they normally have a complete price for installing it.
Second, eliminate that you just have enough FLUID in the radiator in the first place, sometimes (though hardly) the THERMOSTAT can show weird temps when the fluid is low, but (like I said) hardly.
Third, if you're not smelling ANTI-FREEZE in the cabin, it's NOT a leak.

A thermostat in under $15. But to install it yourself can be tricky, depending on where it's located. Excess pressure gets depleted when you exhale the system by turning on either the heater or air-conditioner. You're most likely to get to where you're going when OVERHEATING if you turn on the HEATER instead of the A/C.

If you're going to do it yourself: E-mail me, and I'll send you the instructions. Once you do it yourself, you'll wonder why you ever paid anybody $100 to do it before.

So, in short, you'll need: 1. Thermostat; 2. Matching GASKET for your car model; 3. A razor blade; 4. Two (2) gallons of Anti-Freeze, and a cold engine.

... more

Answer 5

When you turn on the A/C the fan relay is activated and turns on the cooling fan. When the A/C is off the cooling fan needs to be activated by the coolant fan sensor. The sensor may be bad, or thermostat, or low on coolant and not activating the fan sensor,
you first need to make sure the coolant is full then let the car warm up with the A/C off and see if the fan comes on. The fan sensor should go to ground and activate the relay and the fan will run.
Dave (Shop Owner)

Answer 6

Could be as simple as a cooling fan not working on low speed, relay or fuse or fan motor itself. Listen to a known good car cooling fan when it kicks on no a/c on and then turn the a/c on. Or have a technician inspect... some of us are really nice if you get to know us.Tune-up is only necessary on pontiac grand-am gt when you get a engine misfire code and check engine light or a driveability problem. Spark plugs and wires last 60 thousand miles or more.

Answer 7

I,m inclined to think you have a bad ECT(engine coolant temperature) sensor. Two inputs make the fan run and they are the A/C input which from your description seems to be functioning correctly and the other is the ECT sensor that is designed to kick the fan on at a predetermined temperature. And as you say the fan works with the A/C input then I would be inclined to think that your ECT sensor may not be reading correctly.Take it to a good repair facility and have them scan the engine control computer and see if this (ECT) sensor is reading correctly. Good luck.

Answer 8

Start with the cheapest parts first. Check your radiator cap and hoses. Although it's probably the thermostat and/or the water pump. Sorry I couldn't be more help.

Answer 9

examine radiator see if finished get rid of radiator cap chilly engine, if low fill up with engine operating and heater on. If low take back after refilling and get stress examine on cooling device, would have leak, also you should have had thermostat replaced at similar time.

Answer 10

u mean when u trun on the heat the car cools down that bc it takes the heat from the enigine and transfers it to the inetior