MUST AND MILDEW ODOR CAUSE AND CORRECTION

Vehicles reported exhibiting a must and/or mildew odor were found to have water leaks, which allowed moisture accumulation within the vehicle. The presence of moisture allows bacteria to grow which produces the odor in the vehicle.

Superficial cleaning will not rid the vehicle of the odor as the bacteria (source of the odor) must be completely destroyed. The bacteria will permeate all soft trim and porous areas within the vehicle and cannot be camouflaged with a coverup deodorizer. The cleaner smell may fail to hide the odor completely and inferior cleaners are totally ineffective in getting to and destroying the source of the odor.

Trim replacement is not necessary, as an experienced carpet cleaning company specializing in automobile interiors can successfully destroy the bacteria, utilizing a steam cleaning process.

It is recommended you use a cleaning company who specializes in steam cleaning and deodorization, as it may be necessary for the vehicle to be fogged with a germicide to clear up severe odor conditions.

Must and mildew odors fall into two (2) categories: minor or strong. The first six (6) steps in the recommended procedure are to be utilized in handling both categories, with the additional two (2) steps for strong odors.

MINOR AND STRONG ODORS

1. Remove the seats, carpet and underpad.

2. Locate and eliminate all water leaks.

3. In all cases, replace the entire underpad with new material. Order from General Motors Parts Department, P/N 1721689, and trim the material to the required size.

NOTICE: This material is lcm (3/8") thick. If original material is thicker than this, two (2) layers may be required.

4. Wash the floor pan with a disinfectant solution (Lysol or equivalent).

5. Contact and arrange for a cleaning firm to clean, using an industrial upholstery cleaner, the seats and carpet while still removed from the vehicle, as well as the vehicle's interior, door pads, headliner, etc.

6. Reinstall all interior trim pieces along with the new underpad.

At this point, most odor conditions will have been eliminated.

STRONG ODORS

For strong odors or comeback, these additional steps are required:

1. The cleaning company should fog the interior of the vehicle with a germicidal chemical (industrial deodorizor or equivalent). This may have to be done at their place of business, depending upon the strength of the chemical used.

2. Insure the cleaning firm uses a neutral material which leaves no lingering smell.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.