Secondary air injection system, code P0411

Your welcome

See if the check valve at the exhaust pipe is good, where the air injection feeds into. Usually a secondary air fault is due to the check valve being bad, allowing ehxaust to travel back into the air system. Can you hear the air pump run when engine is started cold?If not use a test light to see if it is getting power.

1st check the related fuses. If have a scan tool use it to turn the air pump on. The air pump and air pump relay are located on the driver side frame rail just bellow the drivers door. If that bi-directional communication is not available on your scan tool you can ground the brown wire on the air pump relay and turn the key on. This should turn the pump on if the relay is working the wiring to it is intact and the pump is in working order.

Now that the air pump is running open the air solenoid. You should hear a difference in the sound of the pump. Another way to verify it is opening is to unhook the fresh air pipe from the air cleaner assembly and feel for a vacuum when the solenoid is commanded on. If the valve is not opening try tapping on it when you command it open. If your scan tool does not support this option you can jump the relay in the under hood fuse box. However before removing the valve verify that you have power and ground when you are commanding the air solenoid open.

You may find that the supply pipe from the air pump to the valve is full of water. If this is the case make sure you blow out the lines before replacing any parts

Also incase all checked ok

Repeat SES Light due to a P0410 DTC - Possible O2 Sensor

Models: 2004-2005 Buick Rainier

2004-2005 Chevrolet TrailBlazer

2004-2005 GMC Envoy

2004 Oldsmobile Bravada

2005 Saab 9-7x

with 4.2L Engine (VIN S - RPO LL8)

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Currently, the SI diagnostics do not mention the position 1 O2 sensor as a potential cause of a P0410 DTC.

Recommendation/Instructions:
If the SI diagnostics do not isolate the cause of a P0410 DTC, there is no sign of dirt or water in the AIR pump or relay, and proper AIR check valve operation is noted, replace the position 1 O2 sensor.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

Its about right
check the hose if full of water (drain )
tap on the valve (check if stuck)

Check coolant if low add as needed and check for leaks
if not suspect bad thermostat

Typically its the relay for the secondary air pump that goes bad. I think if I remember right its located near the frame rail on the driverside?

If you have a test light I would check to see if your getting power to the pump at the connector. What are the codes that come up with scan tool?

PCM monitor engine temperature on start up a lazy thermostat would take longer for the engine to reach operating temp setting a code