Lexus is now offering an extended warranty for the below in the United States, released after this blog was written.  Please contact your local dealership with questions and applicabilty.  CARspec no longer performs this repair.  If you have paid out of pocket for this repair, please contact your local dealership to discuss potential reimbursement, as applicable and at the discretion of Lexus/Toyota corporate.  The below is left as originally written.

The 2010 – 2013 Lexus GX460 is susceptible to a common problem with the secondary air injection system, specifically the air filter for the system can fail, be shredded by the pump and the resulting debris thrown into the air injection valves.  For the unfamiliar, the truck’s secondary air emission system is used shortly after startup to clean up the extra fuel the engine needs to get running and has the benefit of speeding up catalyst warmup.  It does this by pushing outside air into the exhaust manifold before the catalytic converter (this air then combines with the hot, unburned extra fuel in the exhaust to finish combustion).  The air being injected starts at the air pump, travels through two air lines to an air injection valve on both engine banks, and then is allowed into the exhaust manifold.

The filter in the air pump is down below, new pump on the left, old on the right looking into the air pump intake.  Note the old pump is missing the filter entirely:

GX460 air injection pump

GX460 air injection pump

The foam filter has been shredded by the pump and thrown into the lines and valves.  Here’s a look down into the exhaust side of the Bank 1 valve.  The debris pictured has already traveled through the valve, causing the failure and check engine light.  It only takes a little:

Air Injection Valve Debris

Air Injection Valve Debris Outside

Valve Debris

Valve debris with cover removed

The failure of the filter requires, due to the extant the debris penetrated the system’s line and valve, the replacement of the pump and both valves.  Lexus redesigned all three parts (the pump and the two valves) to help prevent this happening again.

As Minneapolis’s independent Toyota and Lexus repair specialist we see this problem more often than most and can quickly diagnose and replace the pump with new valves.  If you’ve got a GX460 with a check engine light, give us a call at (952)426-4798 today!