3 Ways to Remove Bugs, Tar, and Sap from Your Car - wikiHow
Rub WD-40 on the body of your car. This oily substance will loosen the dead bugs and help them come off more easily. Apply it to your car's body with a rag or using a spray can and let it sit and soak in for about 10 minutes. Don't use WD-40 on your windshield or windows.