Hello everyone. I am new to this forum and I read through it a lot and found lots of useful things but now I came to a dead end and can't find a problem ANYWHERE. So a few weeks ago my 2006 G35 coupe randomly started overheating so I turned it off and let it cool down and then started it and it was fine, then two weeks later it started having the same issue but letting it cool off would not help anymore so I contacted a mechanic and he told me that my radiator is cracked so I changed that (it wasn't cracked) and changed couple bad hoses with cracks and put in fresh thermostat and did everything by the book and that did not solve my issue so I was back under the hood looking for issues and so my heater stopped working so someone has suggested it's my thermostat so I went and got that replaced and now the car still overheats and my cooling fans seem to not turn off. What could this possibly be. Please someone help me I have no options left (I am not a mechanic and only work on my cars) THANK YOU!

 

You still have air in the system.

Something was bad originally (maybe you did have a small crack in your rad, or a bad cap) and let air in, now that the system has been opened, it needs to be bled properly. Please tell me you didn't let it get to the top (H) of the guage when it overheated.

 

You need to use our SEARCH, "Overheating" has been discussed a gazillion times! Since there's only half dozen possibilities figuring it out shouldn't be difficult...Gary

 

Maybe I did have a crack but I did install the radiator. And no the car didn't quite reach to (H) I would turn it off before that would happen.

 

Cool. Well, search how to purge the system of air, follow the steps and let us know if it solves it. This car is a pain to get the air out of the system cuz the radiator isn't the highest point of the cooling system. Let us know!

 

Everyone thank you SOO MUCH for your help! I had a question so I looked up on how to purge the system (air bubbles from radiator) and everywhere it says to put your car up on the ramp and run it without the cap. Can anyone explain to me why you have to put it on the ramp? I am not a mechanic so sorry if I sound stupid.

 

Well you don't have to. That's just one method. You need the system open at its highest point. If you put it on ramps then the radiator becomes the highest point. If its on flat ground then the bleeder screw is the highest point

 

Gdirtyfive thank you soo much man. Hopefully this works. How do I know that all air has escaped?

 

You have to turn your heater on full blast (90 degrees and full fan). When you feel hot air coming out of the vents you should be good. If you can have someone sit in the car to keep an eye on the temp it makes it a lot easier. Just keep the car on, BUT tell them to turn the car off if it goes above halfway on the guage.

Basically you're gonna keep filling it with your coolant mixture til it won't take any more. Squeezing the lower radiator hose (while the car is OFF!) helps squeeze some of the air out.

The heater check is important. If the heater is on and there is still air in the system it will blow cool air. If you're blowing cool air, you've still got air in the system.

 

So I did EVERYTHING you recommended and it still seems that I can't take the air out. Because my radiator seems to be pretty full and expansion tank is at the max but it is still blowing cold air. Any other suggestions? I am really getting frustrated with this.

 

OK, forget the ramps. Take your engine cover off and use the bleeder screw.

On the he passenger side up by the firewall, theres a rubber hose with a big plastic screw sticking up off of it. Its got a big Phillips head notch. When you're bleeding the system take off that screw and the radiator cap while the cars running and fill til it won't take anymore.