Stupid question about coolent

radiator hose super hot light on dash indicates temp. running bad wants to die in hot weather not sure about filling with water and coolent no cap on radiator weird round fill tank by fire wall with same temp shape as on the dash. can i just fill it up there or not? im a chevy man jettas confuse me.

Owner’s manual should explain this procedure. Sounds like you need to get this to a mechanic who is more comfortable working on a V-dub.

You can put 50/50 antifreeze in the tank on the left with the large blue cap, only if the car is COLD. And you should then get it immediately to a mechanic, if it was running badly you’ve overheated it.
http://image.europeancarweb.com/f/8955472+w750+st0/epcp_0709_02_z+2006_vw_jetta_20t+engine_view.jpg

the temp. gauge never got to high just that light that came on. so i can fill it in that round tank that goes straight to the engine? thanks for your help

Fill it to the ‘full cold’ mark on the side.

Is there an actual RADIATOR CAP you can open and fill or is the overflow tank the only pathway to add coolant??

I’m pretty sure the overflow tank on VWs is the only way to all coolant to the cooling system. It was on my GTI.

theres no radiator cap only the overflow tank, it confused me because its not conected to the radiator it goes to the side of the engine.

thank you again everybody for all of your help i just found this site today and it has helped me out alot.

It’s technically an expansion tank. It is an external visual level indicator and the fill point. They’re actually a throw back from before the 60’s, but in the past decade there’s been cause to seal the cooling system from coolant/air interaction. The “overflow tank” can’t do this.

Note: I believe your radiator calls for G-12 coolant. It should not be mixed with any other kind of coolant! Mixing can cause problems. Check your manual to be sure. Not following this advice can cause head gasket problems. You may want to check compression on all the cylinders to make sure you don’t have that problem.