Some 2005-09 GX470 and 2006-07 LX470 SUVs may illuminate the check engine light and store one or more of the following air injection system trouble codes in the PCM: P0412, P0418, P1440/P1443, P1441/P1444, P1442/P1445, P2440 and P2441.
One likely cause for the trouble, Lexus reported, is a damaged air injection pump or pump filter.
To make the right diagnosis, check the pump for broken fan blades and the filter for disintegration. If you see either condition, replace the pump with an upgraded unit, Part No. 17600-0F010.
Also, be aware that there's a good chance that the debris from the damaged pump has worked its way downstream into the air injection system, which means the main air switching valve along with the No. 1 and No. 2 air switching valves may be contaminated. These components will also have to be replaced depending on what you find during inspection.
Here are the relevant parts you may need to get the fix right:
- Air switching valve – Part No. 25710-50021
- No. 1 air switching valve – Part No. 25720-50011
- No. 2 air switching valve – Part No. 25720-50020
- Intake gasket (cylinder head one) – Part No. 17171-50030
- Air tube gasket (two per valve) – Part No. 17377-50010
"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected].