black sticky tar like substance under car

[Dsun]

So i noticed a black tar like sticky substance underneath my car. Not a whole lot, just a streak here and there or a few spots, its not gooy but semi-hardened but if you pick at it you can get it a bit off. Spots found are the battery tray area, and a few random spots around the floorpan. Could this be aftermarket rust proofing? No signs of rust repair or rust unless the PO did a great job restoring it to look OEM. It was really hot yesterday as well 90 degrees with high humitity..maybe the heat just softened the oem rustproof/undercoating? e30 is 1990 with 115K miles

[MattAvino]

Pics please.
Probably something that came up off the street.

[roguetoaster]

Yes, probably from hot repair patches or other road tar. But could be aftermarket rustproofing. Did you want to remove it?

[Dsun]

what are "hot repairs"? Does that mean welding? Dont need to remove its not really a big deal

[accident]

Sounds like winterization. My Canadian spec car has plenty of it.

[roguetoaster]

No, I meant tar repair patches on the roads, you know those strips that run across cracks and the globs of black in the road.

[Dsun]

its rustproofing. yay