Since the severity of the condition varies from area to area, proper diagnosis of the damage extent is critical to the success of repairs. Perform diagnosis under high intensity fluorescent lighting, on horizontal surfaces, hood, roof panel, rear compartment lid after the surfaces have been properly cleaned. There are 3 basic types of acid rain damage:

Surface Level Contamination: May be repaired by simply washing the vehicle, cleaning the surface with a silicone, wax and grease remover, neutralizing acidic residue and finesse polishing. Refer to Surface Level Contamination Repair.

Clearcoat Etching: Slight etching still noticeable after the above washing and finesse polishing procedure. Refer to Slight Clearcoat Damage - Wet Sanding, Finesse Polishing.

Basecoat Etching: Severe etching beyond the clearcoat into the basecoat.

Slight Clearcoat Damage - Wet Sanding, Finesse Polishing

Caution:  Removing more than 0.5 mils of the clearcoat can result in early paint failure. The clearcoat contains ultraviolet screeners. Do not finesse sand more than what is required to remove the defect.

Note: Always refer to manufacture's packaged instructions for the detailed procedures of materials used for compounding or polishing.

1. Select a small test area on the damaged panel.
2. Readings of the paint film build should be taken prior to the operation. Refer to Paint Gages.
3. Wet sand the damaged area using an ultra-fine sandpaper and rubber sponge sanding block. Refer to the manufacturer's instructions for detailed procedures for the materials used in the repairs. During the wet sand process:

•	Use ample amounts of water.

•	Work slowly in order to prevent removing too much clearcoat.

4. Remove the excess water with a rubber squeegee and inspect the area. If wet sanding has repaired the damage, continue the sanding procedure on the entire panel.
5. Apply a finesse-type polish with a foam pad. Remove any swirl marks with a dual action orbital polisher and foam pad. Refer to Clearcoat Repair Specifications - 3M Products or to Clearcoat Repair Specifications - Meguiar Products. If, during the repair, you suspect or observe that etching has penetrated into the basecoat, too much clearcoat has been removed during sanding or base color is transferred to pad during polishing, the affected areas may require clearcoat/basecoat application or refinishing.
6. Polish the entire vehicle after all damage has been repaired.

Surface Level Contamination Repair

Caution:  Removing more than 0.5 mils of the clearcoat can result in early paint failure. The clearcoat contains ultraviolet screeners. Do not finesse sand more than what is required to remove the defect.

Note: Always refer to manufacture's packaged instructions for the detailed procedures of materials used for compounding or polishing.

1. Thoroughly wash the repaired area with Liquid Wash and Wax GM P/N 1052870.
2. Dry the area thoroughly.
3. Clean the affected area with silicone, wax and grease remover.
4. Neutralize left over acidic residue by cleaning damaged areas with mixture of baking soda and water, 1 tablespoon of baking soda per 1 liter or 1 quart of water. Rinse thoroughly and dry the panel completely.
5. Apply finesse-type polish with a foam panel. If damage has been repaired, remove any swirl marks with dual action orbital polisher and foam pad. Refer to Clearcoat Repair Specifications - 3M Products or to Clearcoat Repair Specifications - Meguiar Products.
6. If some damage remains, refer to Slight Clearcoat Damage - Wet Sanding, Finesse Polishing.