has anybody used such chemcials before? for reason have have 2 spots on my door panel with some tar like substance stuck on it...it's nothing serious but i was wonder if those tar remover really wrong? if so..do those chemcial do any damage to the colours?

 

If you're talking about stuff that's labeled "bug and tar remover" that's fine. Just make sure to re-apply your wax or sealant in the area that you used it, as the chemicals may (likely will) strip that, along with the tar and bugs.

 

I've used Stoner's Tarminator for years. Just make sure you re-apply your wax or synthetic in that area.

 

I am almost embarassed to say that a turtle wax product is good, but Turtle Wax Bug & Tar Remover works really well. As everyone else said make sure to reapply wax or polymer after use.