95 lumina overheating problem

i just finished replacing the head gaskets and when i started the car it was fine for a minute then overheated.i have replaced the thermostat and the water pump but still have the problem.i have added coolant more than once it should be full but it always needs more.i dont know where the coolant is going.i see no leaks and its not going into the oil.please help a frustrated and confused guy who dosent know what else to try.

i just finished replacing the head gaskets and when i started the car it was fine for a minute then overheated.i have replaced the thermostat and the water pump but still have the problem.i have added coolant more than once it should be full but it always needs more.i dont know where the coolant is going.i see no leaks and its not going into the oil.please help a frustrated and confused guy who dosent know what else to try.
did you relace the intake gasket? mine was taking coolant and didnt seem like it was in the oil, but when i took the intake off coolant every where.. also check the heater core..

I guess you bled the system properly?

yes all gaskets were changed but is it possible there may be an air leak somewhere??

IF it's overheating very quickly, then you still have air in the cooling system. Bleeding all the air can be a time consuming PITA on these engines.

how long can it really take to get out the air??i had a stream of coolant coming from the bleed screws.i thought all the air is out but i will try again.thanks for the idea.at this point i will try anything to get my car going again:grinyes:

well i tried bleeding the system until all the air bubbles stopped coming out of the bleeder screws.its still getting hot:banghead: could there still be air in the system or is this something else?im not losing coolant and am getting heat until the guage gets to about 3/4.now it drops to 1/2 temp then back to3/4 and never going down to normal.what now:frown:

how long can it really take to get out the air??i had a stream of coolant coming from the bleed screws.i thought all the air is out but i will try again.thanks for the idea.at this point i will try anything to get my car going again:grinyes:theres 2 bleeder plugs one on the thermostate housing the other on the heater pipe,, with the car runing open one at a time untill you get all coolant out,keep repeating..your gauge shouldnt reach 1/2 way mark...

ive got coolant coming out of both of them but i will try again tomorrow.is it normal to have to bleed it more than twice?

ive got coolant coming out of both of them but i will try again tomorrow.is it normal to have to bleed it more than twice?
after 2 times it should be ok.. it could be the head gasket miss algined.. have you ever replaced one before.. it seems the coolant isnt circualating.. squeeze the top radiator hose and see how much pressure you feel..

after 2 times it should be ok.. it could be the head gasket miss algined.. have you ever replaced one before.. it seems the coolant isnt circualating.. squeeze the top radiator hose and see how much pressure you feel..yes i have replaced 2 head gaskets on 3.1L engines and never had this problem.when i squeese the upper rad hose there is alot of pressure.if the head gasket was miss aligned would i not see coolant leaking or in my oil?

wow now im confused.i had the car at normal temp when sitting in the driveway,when i went out for a drive it overheated within minutes.the resivoir tank was full to the top when i shut it off.any ideas?can i tell if the head gasket is sitting properly without taking the engine apart again?

wow now im confused.i had the car at normal temp when sitting in the driveway,when i went out for a drive it overheated within minutes.the resivoir tank was full to the top when i shut it off.any ideas?can i tell if the head gasket is sitting properly without taking the engine apart again?
did you put a new intake gasket on? is the car taking coolant?is the thermostate in right? if you put head gaskets on before you should know..if anything its the water pump..or radiator blocked....the head could be blocked,, just keep working with it..

did you put a new intake gasket on? is the car taking coolant?is the thermostate in right? if you put head gaskets on before you should know..if anything its the water pump..or radiator blocked....the head could be blocked,, just keep working with it..yes i replaced the intake gasketsand the car is taking coolant.the thermostat is in properly.i put head gaskets on before but i never ran into this problem.im thinking this is not a problem wit air in the system.could the head gasket not be sitting properly?would this cause my problem?anyways i thank you for all your suggestions.if you have any more greatly appreciated if not like i said thank you for your help:grinyes:

yes i replaced the intake gasketsand the car is taking coolant.the thermostat is in properly.i put head gaskets on before but i never ran into this problem.im thinking this is not a problem wit air in the system.could the head gasket not be sitting properly?would this cause my problem?anyways i thank you for all your suggestions.if you have any more greatly appreciated if not like i said thank you for your help:grinyes:
chris... it is not air in the system.. your coolants going into the engine oil.. the head gasket or intake gasket is miss aligned a water jacket mat be coverd.... if your coolant was boiling out it would be a differnt story.. blocked radiator or etc..

chris... it is not air in the system.. your coolants going into the engine oil.. the head gasket or intake gasket is miss aligned a water jacket mat be coverd.... if your coolant was boiling out it would be a differnt story.. blocked radiator or etc..you may be right.thats what i was afraid of.lol.i guess ill take it all apart again and see what the heck is going on.thanks for all your help and i will let you know how i make out:grinyes: :grinyes:

chris... it is not air in the system.. your coolants going into the engine oil.. the head gasket or intake gasket is miss aligned a water jacket mat be coverd.... if your coolant was boiling out it would be a differnt story.. blocked radiator or etc..i was afraid you would say that:disappoin i must have messed up when i put it together.iwas hoping it may be something simple but what can you do:lol: i guess ill take it apart again and see what is going on.thank you very much for all of your suggestions and ill let you know how i make out.

i was afraid you would say that:disappoin i must have messed up when i put it together.iwas hoping it may be something simple but what can you do:lol: i guess ill take it apart again and see what is going on.thank you very much for all of your suggestions and ill let you know how i make out.
chris... just take your time with it, the gaskets may be reusable..before you tear it down take out the plugs see if theres coolant on them, if not it may just be the intake gasket misaligned..the head gaskets usuly dont go on the 3.1 or if they do its after you get the engine red hot.. then the head warps....iv got a hunch its the intake gasket...

chris... just take your time with it, the gaskets may be reusable..before you tear it down take out the plugs see if theres coolant on them, if not it may just be the intake gasket misaligned..the head gaskets usuly dont go on the 3.1 or if they do its after you get the engine red hot.. then the head warps....iv got a hunch its the intake gasket...what would happen if coolant was going into the intake?would it just get so hot and boil away?if i do use the same gaskets do i put a little bit more silicone than normal?the spark plugs are bone dry.i thought i would check before i sent this.i think you are right and it is an intake gasket.

what would happen if coolant was going into the intake?would it just get so hot and boil away?if i do use the same gaskets do i put a little bit more silicone than normal?the spark plugs are bone dry.i thought i would check before i sent this.i think you are right and it is an intake gasket.
dont put any silicone on the gaskets, the coolant is going in your oil, did you ckeck the oil?

yes i checked the oil and it looks fine and is at the same level as when i filled it.no silicone on the gaskets?the manual says to use a thin bead on the intake gaskets.why should i not use any?

yes i checked the oil and it looks fine and is at the same level as when i filled it.no silicone on the gaskets?the manual says to use a thin bead on the intake gaskets.why should i not use any?
not on the gaskets, at the end of the intake only use silicone..

I have the same identical problem. I haven't replaced the head gaskets though. But I have replaced the thermostat and sensor. What is really weird is when I first fixed it it ran fine for a day or so and now if I drive around the block it overheads again just like yours. I am lost as well, bled system etc. And sense you already replaced the water pump and have the same problem I can't see doing that.

If you solved your problem I would be grateful for a reply. If I solve it I will get back to forum. If anyone else has any ideas I would be grateful as well.

I can also be emailed directly at [email protected]

I have the same identical problem. I haven't replaced the head gaskets though. But I have replaced the thermostat and sensor. What is really weird is when I first fixed it it ran fine for a day or so and now if I drive around the block it overheads again just like yours. I am lost as well, bled system etc. And sense you already replaced the water pump and have the same problem I can't see doing that.

If you solved your problem I would be grateful for a reply. If I solve it I will get back to forum. If anyone else has any ideas I would be grateful as well.

I can also be emailed directly at [email protected] i have not solved the problem yet but will let you know sometime next week after i take it apart again.

well i took the whole engine apart again and didnt find any cause for the overheating problem.i replaced all the gaskets with new ones not taking any chances.put the engine back together again and it ran fine...for about three or four hours and then started overheating again.i had a mechanic help me put it all back together to make sure i was doing it properly and as far as he could tell everything went well.he lives a long way from me so he was not here when i started the car.i bled the system until absolutly no air came out of either bleeder screw.im at my wits end:banghead: could this be some sort of sensor?if anyone has any ideas please let me know.

well i took the whole engine apart again and didnt find any cause for the overheating problem.i replaced all the gaskets with new ones not taking any chances.put the engine back together again and it ran fine...for about three or four hours and then started overheating again.i had a mechanic help me put it all back together to make sure i was doing it properly and as far as he could tell everything went well.he lives a long way from me so he was not here when i started the car.i bled the system until absolutly no air came out of either bleeder screw.im at my wits end:banghead: could this be some sort of sensor?if anyone has any ideas please let me know.
chris.. after i replaced my intake gasket,,a couple weeks later it started showing hot.. i had to replace the temp sensor unit by the thermostate housing,, but do it when the car is absolutly cold.. also if you are runing water in the engine it will run hoter,, i had to drain it and put antifreeze in...put your hand on the top of the engine, see if its hot..

chris.. after i replaced my intake gasket,,a couple weeks later it started showing hot.. i had to replace the temp sensor unit by the thermostate housing,, but do it when the car is absolutly cold.. also if you are runing water in the engine it will run hoter,, i had to drain it and put antifreeze in...put your hand on the top of the engine, see if its hot..well i finally broke down and brought the car to a garage.i hate doing that.lol.they are telling me that there is a crack in the head or ti is warped. i had the heads both pressure tested and machined down.the garage says to take it apart again and if the problem persists it is a cracked block.could this be the problem or should i replace the temp sensor??the garage says exaust is leaking into the coolant building pressure but it is overheating more now then whan the head gasket went in the first place so can it be a crack?if so what can i do?replace the engine ro is therre another way?oh yea the cooling fan does not stay on the whole time the engine is overheating.it seems to be working properly.

well i finally broke down and brought the car to a garage.i hate doing that.lol.they are telling me that there is a crack in the head or ti is warped. i had the heads both pressure tested and machined down.the garage says to take it apart again and if the problem persists it is a cracked block.could this be the problem or should i replace the temp sensor??the garage says exaust is leaking into the coolant building pressure but it is overheating more now then whan the head gasket went in the first place so can it be a crack?if so what can i do?replace the engine ro is therre another way?oh yea the cooling fan does not stay on the whole time the engine is overheating.it seems to be working properly.
why would you have to tear it down again? if it was a cracked block you would be losing coolant.. you said theres no coolant leaks.. is the engine hot hot or is the temp gauge just showing hot.. i had to put a temp sensor on mine a couple weeks after i replaced the intake, the engine was cool but the gauge showed almost 260...

why would you have to tear it down again? if it was a cracked block you would be losing coolant.. you said theres no coolant leaks.. is the engine hot hot or is the temp gauge just showing hot.. i had to put a temp sensor on mine a couple weeks after i replaced the intake, the engine was cool but the gauge showed almost 260...i dont see a coolant leak but there is still compression going into the coolant.the engine is actually hot and the guage says its hot.ive been told to get the heads pressure testedand if they are fine that it is a cracked block.is there any other reason for a compression leak besides a cracked block or a blown head gasket?

i dont see a coolant leak but there is still compression going into the coolant.the engine is actually hot and the guage says its hot.ive been told to get the heads pressure testedand if they are fine that it is a cracked block.is there any other reason for a compression leak besides a cracked block or a blown head gasket?
you dont have a cracked block or head.. you would be losing coolant... check the top radiator hose with the car runing, see if theres pressure there.. then bleed the air out.. let the car sit over night , then reset the cp. drive it and see what it does..

you dont have a cracked block or head.. you would be losing coolant... check the top radiator hose with the car runing, see if theres pressure there.. then bleed the air out.. let the car sit over night , then reset the cp. drive it and see what it does.. i will try this out and see if it works.really ive got nothing to lose at this point.lol.the only thing i want to make sure on is what you mean by the cp?and also how do i reset it?i have checked the rad hose and i do have pressure.why would the car have to sit overnight before resetting the cp?thank you for all your help youre the only one who has told me anything besides a crack in the head or in the block.

i will try this out and see if it works.really ive got nothing to lose at this point.lol.the only thing i want to make sure on is what you mean by the cp?and also how do i reset it?i have checked the rad hose and i do have pressure.why would the car have to sit overnight before resetting the cp?thank you for all your help youre the only one who has told me anything besides a crack in the head or in the block.
just let the engine cool overnight, then unhook the battery and that sets the computer.. dont idle it drive it, come back bleed the air out. it should be alright..

just let the engine cool overnight, then unhook the battery and that sets the computer.. dont idle it drive it, come back bleed the air out. it should be alright..i have already tried letting the engine cool down overnight and bleeding the air out but not disconecting the battery.i will give it a shot tonight and let you know tomorrow what happens.

well i tried exactly what you told me to do and it still overheats.any other ideas?im ready to totally give up and the garage is no help at all.so i cant even take it anywhere to get it fixed.

well i tried exactly what you told me to do and it still overheats.any other ideas?im ready to totally give up and the garage is no help at all.so i cant even take it anywhere to get it fixed.
chris.. i dont know what to recomend.. you had the heads pressure tested and machined its not losing coolant.. and you bled the system, you repaced the temp sending unit.. your car shouldnt be hot..

chris.. i dont know what to recomend.. you had the heads pressure tested and machined its not losing coolant.. and you bled the system, you repaced the temp sending unit.. your car shouldnt be hot..hey you know what...i never replaced the temp sending unit.duh i totally forgot.ill try that and let you know what happens.i think this could have saved alot of time.i dont remember telling you that i did so i will try asap.mabey that was the problem all along.:lol: :lol: :lol:

Chris, I'm having a similar if not the same problem with my 95 Lumina. Do you ever get the Low Coolant light like I do?? I've replaced thermostat, water pump & had dealer replace lower intake manifold gaskets. When idling and you turn a/c on do both fans cycle o0r only Fan #1?? Did you solve it?? Doug

i replaced the temp cooling sensor and the car is running way better.ive got one more sensor to change to see if i can get it running better.im happy with the temp staying just over half but not satisified.i think this problem is finally behind me.lol.any questions feel free to ask or email me.

i replaced the temp cooling sensor and the car is running way better.ive got one more sensor to change to see if i can get it running better.im happy with the temp staying just over half but not satisified.i think this problem is finally behind me.lol.any questions feel free to ask or email me.
chris.. congradulations.. now your officialy a back yard mechanic..... good job...

chris.. congradulations.. now your officialy a bank yard mechanic..... good job...hey thanks...its not perfect but it will do for now.lol.thanks alot for all the help along the way.it was greatly appreciated.hopefully no more problems for awhile.