Thank you for contacting Meguiar’s! Yes, the Car Wash Plus does contain conditioners to enhance gloss and shine but does not contain wax. The main advantage of the Car Wash Plus is its ability to clean tough grime that normal car washes are unable to do while keeping your wax protection safe."
'A really dirty car' can have two meanings. It can refer to surface dirt and dust (Most common usage) or to embedded road film (Where this product is most likely to shine - pardon the pun). I would always rinse surface contamination off before using this product to aggressively remove road film.