I have a 2002 Olds Alero GL my heater is not working and car overheats peoriodically losing antifreeze, please help freezing in Montana

I need more information. Does it lose antifreeze or just simply overheat? If it is losing antifreeze you have a hole in hoses or might need a head gasket or even pump, if it is not losing and it overheats could be a simple thermostat not opening or needs new rad. So I guess I need to know Dows it lose antifreeze and does your heating work?

Could be a blend door problem under the dash.
If one heater hose is hot and the other is not, could also be a blockage in the heater core.

Check the cooolant level, sound like theres a leak somewhere, water pump, hoses, t-stat bad, rad cracked, heater core leaking, bad rad cap, cooling fans not working, you need to get it looked at really soon, before you get it to hot and blow a head gasket.

Your 2000 Olds Alero should have the 3400 V-6 engine...the water pump sells for about $45. The change out does not require the removal of any major components...(ie engine mounts etc.) You can loosen the serpentine belt to gain full access to the water pump bolts...Yes you will lose some anti-freeze and need to refill after replacing the pump...antifreeze $8.50 per gallon...recommend you use antifreeze "Good for All Models" as it has proven to be the best for longevity...Hope this helps...Your estimate is way to high...A shop will mark up the part slightly, and charge for labor...This job should be completed in less than 1 labor hour...$55. to $75. per hour depending on your location...PLEASE shop around if you cannot do this one by yourself:)

sounds like your ABS sensor is bad. The ABS sensor controls the trac. control. but it wouldnt effect daily driving. you would only notice it if you slamed on the brakes on a slick surface. the brakes will lock up like they ARE NOT supposed to.

you should be fine just as long as the replacement part meets emissions standards. You don't actually need one if you don't have to pass an inspection.

Your cooling system needs to be pressure checked to see where the leak is. certain auto parts stores rent out a pressure checker. make sure you have the cooling system full before doing the pressure test. check to see if you have a radiator cap and fill the system that way instead of using the resevoir

in my experience it sounds like a head gasket problem it maybe leaking into the cylinders or could be a small leak from one of the hoses I would do a compression test just to make sure and then pressurize the entire system using radiator and coolant tester if pressure holds then its not a leak as far as the fans go just have the car running when it reaches the middle of the temp gauge it should come one if not you may need to run check on temp sensor or fan switch and fans them selves I would follow repair manual troubleshooting section on heating and cooling haynes or chiltons will do.

problem could be heads bolts . i put new bolts in put a little sealer on them . make sure your bolt holes is clean free from debris. put a lillte sealer on intake gasket on top and bottom where coolants travel. if all was done . drain engine oil in clean container .set it aside. take radiator cap off .you a coolant pressure rise kit .put a pan under oil pan with drain plug still off .pressure your radiator about 10 psi. make sure you have antifreeze in radiator and engine . when you pressure up to 10 psi look under the car if coolant comes out oil pan. you got leaking head gasket. if not .put oil pan plug back on . put oil back in car . check your freeze plugs also.

When you say not leaking antifreeze has your coolant level gone down at all? and is it that you have seen no leaks where you park it? What worries me is you can smell it when warming up, have you felt the interior floors to see if damp and do you get any condensation if put blower onto screen, if so then heater matrix is leaking if not could be down to headgasket and/or cylinder head leak.