My 96 has a rough idle and it's getting on my nerves when I sit at lights. I went to PepBoys and bought some throttle body cleaner only to realize that my thottle body clearly states not to clean the throttle plate because of a protective coating. The stuff I bought (penzoil) claims that it won't remove protective coatings. Should I go ahead and use it anyway? I'm hesitant becauae i don't have any money right now. Does anyone have any info???