Remove weird stuck-on substance from windshield

Question

On a recent trip, while sitting in the passenger seat, I noticed something strange by the edge of the windshield. At first I was afraid that the windscreen got chipped, which would be upsetting given the car is only a few months old. However, when we stopped and I looked at it, I saw that it was a globule of something gooey. I managed to take most of it off with my hand (don’t know if touching it was the best idea but there we are), but it left a residue.

I forgot about it until I was cleaning the car recently. I tried to rub the residue away using a micro fibre cloth and Meguiar’s Quik Detailer, but no luck. It feels very solid and stuck on. If I had to guess, I would say it was some kind of glue, but I don’t know for sure.

I’m attaching the best photo I could take of this thing. I apologise if it’s blurry, my phone was struggling to focus on it.

Any hope of taking it off? I haven’t yet tried glass cleaner. A quick internet search also suggested Goo Gone, but I wanted to get someone else’s opinion before going out to buy that.

It probably doesn’t matter, but the car is a Tesla Model 3. Appreciate any help!

update: Glass cleaner took most of it off, but there is still some residue left. Not sure if harder scrubbing will take it off, or if I need something else. But either way, it’s significantly less noticeable now.

Answer 1

Maybe it's tree sap?

You might try masking tape. Its own adhesive isn't very strong, but I've had good results using it to remove adhesive residues (dashcam mounts). Take a strip and touch the adhesive side to the residue, then remove it, and repeat; it's like you're trying to pick something up with the tape.

I've used various solvents on Model S glass without any noticeable problems: ammonia-based glass cleaner, acetone-based nail-polish remover, and whatever is in Trader Joe's "multipurpose" cleaner. Whatever you try next, it might be a good idea to try to soften the stuff up: dampen a clean cloth and leave it on there for a few minutes.

EDIT: but there are some warnings about ammonia here: Is Windex safe for the windshield?

Answer 2

Tree sap does come to mind; I have that occasionally in my driveway.

Using a paper towel, I'd try WD-40, paint thinner, or lacquer thinner. None will harm paint or glass, and one or more is likely to dissolve whatever it is.