Just got a 2002 Blazer extreme and today while we were driving it the heat wasn't really working. Then it bagan to overheat we pulled off and the coolant reservoir was still right were it should be began driving again letting it cool off and every time we started it again the temp would just shoot back up. Finally figured out that the radiator was empty but reservoir was still good. I was wondering would could cause that to happen cause when the reservoir was filled the radiator also was. No spots of antifreeze on ground after it is parked. Sorry if i couldnt explain it very well and if you have any other questions i will try to answer them the best I can but im not the most mechnically inclined person. Thanks for the help in advance

 

I would say replace the radiator cap first, that's what comes to mind first to me, I had that happen to me in other car and it was the radiator cap.

 

Check if the hose from reservoir to radiator is clear... Then try a new cap.

My 97 has had some gunk buildup on the cap and around/in the hose hole. And inside the reservoir used to look real dirty, before a full flush.

 

Thank you very much i will try that as soon as possible and see how that works.

 

So we have replaced the cap done a flush and also changed the t-stat. it ran fine for a little bit but it now we have antifreeze disappearing. and it is also draining the overflow also. so we did get that fixed the hose was clogged. there is still no signs i can see of leaking anyway. Ive read that it could be the intake manifold gasket. Is there anyway of testing to see if that is what it is or if there is any other things it might be. Thank you very much for your help