Stubborn paint stains (pics included)

[Driven Auto Detail]

Hey guys, hoping you can possibly help me on this one. Silver Dodge Charger that belongs to one of our local detectives. The Town Garage called me this afternoon and said it looked like the car had "sat under a walnut tree or something". There are some strange rust-colored stains all over the front end of the vehicle. Had them bring it over to the shop for me to check out. In my head I was thinking, clay bar or possibly some Tarminator should do the trick. Fast forward to post-washing and neither of those options even touched the stains. I cannot feel the stains when I rub my hand across the paint. Here's what I've tried so far:



Aggressive clay bar

Tarminator

Mineral spirits

M105/5.5" orange pad on DA

M105/W4000 wool pad on rotary

Menzerna Power Gloss/W4000 wool pad on rotary

2000 grit wetsanding by hand



Only wetsanding and compound/wool/rotary even began to touch it. As you'll see in the last picture, even after 2000 grit wetsanding one of the many stains on this vehicle, the stain still remained.



I'm at a loss on what to do. If I can't fix it (which looks to be the case), I'd still like to be able to refer them to their next option, which I'm guessing would be the body shop for a re-paint if they want to go that far with it.



Sorry for the blurry pics. All I had with me was my Blackberry Bold.

After wetsanding with 2000 grit by hand:

Thoughts? Suggestions?



Thanks in advance!

 

[Lonnie]

My "guess" is that these are bug/larva/catapillar droppings from something eating on the walnut tree and that the droppings, being highly acidic, have burned, etched, and stained their way through the clearcoat and into the pigment of the paint. I would highly doubt that it is some kind of tree sap or leaf discharge from a walnut, but I'm not a tree expert. What makes me think it's in the pigment is the fact that you cannot "feel" the stain, not unlike acidic bird droppings that burn/etch the clearcoat, but it does not feel rough, but looks like a textured stain that is impossible to remove, short of wetsanding (and compromising the clearcoat thickness).

If you do get to the bottom of this mystery (no pun intended, seeing it's a detective's car) let us know. How you're going about fixing this "dilema" would seem to be a logical approach. I would try to fix one spot and maybe "experiment" on that. What have you got to loose? If it works, great, use the same technique on the other areas. If not, a re-paint was the next step anyway.

 

[Driven Auto Detail]

Thanks for the insight on the type of droppings it may be Lonnie. It's definitely a mystery for me. Since posting this thread, I'm looking at a paint decontamination wash system from either Finish Kare. Although, I'm still not convinced that would work either.