Smoke 'em if you got 'em
BMW suggests using a smoke machine to check for vacuum leaks (this applies to all models, all years). First, determine if the vehicle has a condition where the induction system could be leaking (Does the vehicle have adaptation faults? Does the vehicle have oxygen sensor trimming faults? What are the adaptation values, and are they positive or negative?).
In cases where the adaptations indicate a lean condition (positive value), a smoke machine is a helpful tool in determining of the induction system has a leak.
Recently, the VACUTECH Smoke Machine 625-522B-BMW has been added to the BMW Equipment Program. This tool may be ordered by calling 888-222-7997.
Included with the new VACUTECH Smoke Machine are various caps and adapters to help connect the applicator hose to the vehicle. It is always suggested not to disturb the system before testing. Try to disturb the system as little as possible when connecting the smoke machine.
This smoke machine utilizes an UltraTraceUV smoke solution. The smoke solution incorporates an ultraviolet dye that helps to pinpoint the leak with a ultraviolet residue surrounding the leak area. Determining the source of the leak is made easy when the included Hi-Density True UV LED light is used.