Some customers may comment that the Malfunction Indicator Light (MIL) is illuminated and DTC P0420 and P0430 are set.
This may be caused by excessive sand and/or debris entering the air filter box and bypassing the seal of
the air filter, due to not properly sealing, causing damage to the HO2 sensor element and the catalytic
converter to become blocked with sand and debris particles.
Do not replace any of the parts until the air filter housing has been validated to be completely sealed.
If the condition is evident, an inspection of the air box and air filter seal must be done.
Follow the Service Procedure steps in order to verify the sealing of the air filter to the housing surface.
After validating the air box has been sealed, repair the P0420 and the P0430 codes as needed
Catalytic Converter with sand:
HO2 Sensor with sand:
1. Inspect all the air housing cover for any missing tabs and/or fasteners (1).
2. Remove the air filter housing cover and inspect the seal around the air filter (2).
3. Inspect the air filter sealing surface for signs of not contacting the air filter seal (1, 2).
4. Inspect the air filter housing cover for dirt and/or debris bypassing the air filter (3).
5. Inspect the air cleaner outlet duct for any dirt and/or debris.
• If dirt and debris has been found bypassing the air filter due to a faulty seal, replace the air filter, as necessary.
• If the air filter housing has been found not properly sealing, replace the Air Cleaner Assembly,