I changed out the coolant this past weekend and now smell that sweet coolant cooking aroma.
I pulled a vacuum on the system and held it for @ 5 minutes with no drop...I assumed this would indicate that (at that time) there were no leaks. Short of a faulty expansion tank cap is there something I'm overlooking.
2008 xk
WJ

 

I recently read an item where the XK owner had the same smell but could not determine where the leak originated. However, when he ran the engine at "high" idle for several minutes while a friend stood watching the engine bay the friend could see a tiny jet of vapor coming from a pin hole in one of the lines. Apparently this occurred only when the system was under increased pressure?? Worth a try anyway.

 

You MAY be smelling a bit of spillage from when you did the change.

 

Wouldn't pressurizing the system be a better check for leaks? The cooling system operates under pressure when the car is running. Testing under vacuum could find leaks but may tend to seal small leaks like pin holes in hoses.

 

I did spill several drops but really...just drops.
Will watch the level with fingers crossed hoping it doesn't go down.
Pressurizing would be my next step if needed.
Thanks for the thoughts @ this.
wj

 

had the same situation except for the smell, it was a tiny tiny jet on the top side of the engine at the front which, off the top of my head, i think is a reservoir return line.

 

I have the same leak from the coolant reservoir return line,
and i've replaced that line earlier this year, i'm thinking of upgrading the O-ring to a fatter one.
it only leaks under hard acceleration, but why is this leaking??