My 2004 Pontiac Grand prix is overheating and no hot air is coming out. I changed the water pump and the thermostat. I woke up morning the coolent hose was froze and alot of water in resavoir overni
You have an air pocket in the cooling system and not enough anti-freeze mixed with the water. Coolant should NEVER freeze unless it's 50 below.
How do I get the air out
First you have to thaw everything out. A warm garage works nicely. Then you have to get the car running and warmed up with the radiator cap off and wait for the thermostat to open keep adding anti-freeze as the level goes down. you will be able to see the coolant flowing through the radiator. Once it burps out its last bubbles put the cap back on ALL THE WAY tight. Fill up the radiator and over flow to the proper level once the car has completely cooled down.
I did everything you said but now the heat is coming in and out abd the car is overheating some and then goes down
You either still have an air bubble/pocket, the new thermostat and/or water pump is bad(it does happen), plugged heater core or when it got hot it might have did damage to a gasket or head. Let it cool down and take the cap off see if its low again. Check the oil dipstick and see if its overfull and foamy. Check the upper and lower radiator hoses and heater hoses make sure they aren't mushy or collapsed.
Ok thank you so much
No problem. Let us know what happens.
I did as you said the oil doesn't look foamy but it's to the 3 hole I only get heat when I'm going really fast after the car overheats when it cools down the heat goes away
Ok that's very good no coolant in the oil means no blown head gasket or cracked head. Is there a bleeder valve on the top of the thermostat housing? If so run the car with the cap off and the bleeder open (I believe it's an 8mm) just a little bit to get the air bubbles out. Once coolant runs out of the bleeder without bubbles tighten it up. Cap off the radiator and overflow, you should be good to go! Just remember 50/50 mix of anti-freeze and water next time.
Top off the radiator and overflow bucket. Sorry about the Cap typo.
Thank you it got dark and cold I will try tomorrow and sees what happens thank you so much
No problem. Hopefully tomorrow you have heat!
You said run the car with the cap off what cap the radiator cap? Is it possible to be the heating sensor
Yes radiator cap off
Ok should I wait till the car heats up and then take odd the bleeder cap and radiator cap or when I first start the car
Never take a radiator cap off of a hot car. You will get burned. Cap off, bleeder open not off before you start it up.
Oh ok I figured that thank you alot what's happening now is the the car won't overheat when I'm driving fast the Guage goes down and the heat kicks on ass soon as I stop the gauge goes up and the heat goes out
Did you use the bleeder valve on the thermostat housing? You left it open until bubbles stopped coming out? You filled up the radiator and overflow bucket? Sounds like you still have an air bubble or the heater core could plugged up?
Yes at least I thought I did and yes I keep refilling the radiator for some reason fluid comes back into the reserve way more than I had in there like way more
Ok that's what the overflow is for. When the radiator overflows it goes in the bucket then the radiator sucks it back out when needed. That's why you don't overfill the overflow bucket when adding anti-freeze. Let the car cool down again. Open the radiator add anti- freeze if needed. How long have you been letting it run while burping the air out?
About 5 10 minutes
Ahhh there is our problem. It should take at least 15-20 minutes for the thermostat to open up and fully circulate when its cold like this.
Oh ok thank you so much
Ok so I did that again and still overheating no heat do you think it could be the coolent sensor
Yes it could be a bad temp sender but more importantly is the no heat. You might have a bad heater core or an air pocket still. What do you think Fordnut? BTW thanks for the picture.
Yea the picture was very useful and I did hear about the heatercore
I also heard that if the gauge goes down when I turn the heat (no heat) on then the heater core is fine
If the temp goes down it means the thermostat is opening.
Sounds like air in the system to me too. You may want to take it to a shop and get the coolant drained and refilled there. They have special vacuum tools designed to draw the air out of the system while it is being filled. For some reason modern cooling systems are a lot more difficult than they used to be.
Thanks munron. Good answer.
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