2001 Mazda Protege ES 2.0, 2015 Mazda3i Touring
Hey guys, new to the 6 scene so don't be too harsh. I have a pretty weird discovery.

I just purchased my '05 6s (auto) 164k about a month ago and I've spent a little money getting it up to snuff to my liking.
New tires, tracked down a pretty nasty coolant leak and replaced those parts, tried to diagnose the notorious "oil burning smell in cabin" that these V6 engines seem to frequently have. May have a small leak at the timing cover seal but nothing bad enough to be worried about, I only bought this to get me back and forth to work I have a '15 3i 6MT for the rest of the time.

However, I recently was checking my oil (because I periodically check it more frequently now because of the leaking oil), full, but I noticed a neon green liquid on the threads of the oil cap. I wiped it off, went for a drive and it was back again. I found this very odd because I have global gold coolant, my oil on the dipstick is pristine, no white smoke and no overheating so I can't imagine it's anything within the head gasket realm, oil mixing with coolant, etc... The previous owner and shop they used had previously used blacklight dye to track down a different oil leak, but I didn't think it was a lime green color, especially not under just direct sunlight at least.

Anyone able to shed any light? I included a pretty poor picture, the color in person is a vibrant lime green - not milky at all.


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