If you have a touchless automatic or tunnel, there are things you may not be aware of.
Five major factors come into play when you clean without friction.
First is water quality. Water must be soft (0 GR) for the soaps to work properly. Most soaps have some softening agents in them, but this is an expensive way to soften water.
Second is temperature. Soaps work best at warm temperatures. Ideal temperature is around 120 degrees F. For every 10 degrees of temperature, it increases activity by ten times. But, too much is not good either over 140 degrees F soap starts to fall apart and have adverse effects on cleaning.
Third is time, or dwell time. How long the soap is on the car. It needs to be on the car for a certain amount of time to loosen road soils and have some movement.
Fourth is concentration. Touchless cleaning requires soap to be more concentrated or aggressive than soaps in friction car washes. Some use two steps, acid and alkaline, or some are single step, alkaline only. Acids clean the inorganics or manmade items such as brake dust, salt, asphalt road film and magnesium chloride. Alkaline cleans the organics soils such as bugs, pollen, and bird droppings.
The fifth is pressure. Since there is an absence of friction, pressure is what helps remove the road soils. It needs to be high; usually 1000-1100 PSI works best. It also needs to move slowly around the car. Lower wash speeds produce better quality. That is the friction replacement.
All are very important in touchless cleaning. The absence of one or more could cause the wash to stop cleaning. So, check these items above often, especially water quality and concentrations. The others remain fairly constant. Do not over react just because you saw one car with film. If all factors are in line, you may have just seen a car that has not been cleaned in a while, or the hydrocarbons did not release.