I am trying to diagnose a loss of coolant in my '00 and think I may have a cracked head because I couldn't find an external leak. Unfortunately, when I was checking to see how the coolant looked under the black light before adding the dye, I forgot to check to see how the dipstick and under the oil filler cap looked.

After adding the dye and driving around at temperature I scanned the engine with the black light and didn't see any green spots. Then I looked inside the valve cover but it was tough to see anything. However, the underside of the cap and the dipstick were bright white when I shined a light at them. Does anyone know if motor oil glows white under a uv lamp, or could this be the green dye diluted and mixed with the oil? Sorry about the dumb question, but I forgot to check the oil without the dye and now there's no going back and I don't have another car to compare the oil to.

Thanks