2006 Infiniti M35 coolant smell

If you can see it, you have a leak. If you can smell it, you have a leak. The coolant has to vaporize to get to your nose. If you can see it AND smell it, ... Well, ... You have a leak.

Sometimes the leak is so small the coolant vaporizes before it has a chance to run down to where you can see it. A dandy solution for this is to add a small bottle of dark purple dye to the coolant, drive a day or two, then search in the area with a black light. The dye will show up as a bright yellow stain that you can follow back to the source. Auto parts stores will have the dye, and those that rent or borrow tools should have a black light.

For a real slow leak, the water pump is a good suspect.