04 chevy trailblazer air pump not working. what is wrong

Question edited for clarity.
Question moved to model category.

There are three videos that might help. If you can inject Seafoam down it and add a bottle of fuel system cleaner may also help.

https://www.google.com/search?q=Chevy+P0411

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Ull need to scanit w a factorytool at a privateshop. It reads a datastream to pinpoint issues. Those portabl readers are general. Dont just replaceparts n hope. Oldercars can hav worn wireharness causin weird problms too. Unplug computer n cleanpins..dirt is common in aging vehicles creating issues. Since its jyst an emmission thing udont need to worry its runnin too lean or sumthin crucial

have a look here for workshop manual.. http://workshop-manuals.com/chevrolet/

AIR SOL - fuse #54 15amp - AIR fuse #56 60amp location under hood fuse / relay box
54
AIR SOL Fuse
15A
AIR SOL Relay, Secondary Air Injection (AIR) Pump Relay, Secondary Air Injection (AIR) Pump, Secondary Air Injection (AIR) Solenoid
55
AIR SOL Relay
--
Secondary Air Injection (AIR) Solenoid

ck fuse relay pump or wiring

location of air injection pump (smog pump) 2004 chevy trailblazer v6.

before you drop tank again, check fuses & relay.then disconnect fuel line @ filter turn key to on position should hear fuel pump run and get gas stream out of line. if no flow from line new pump faulty be sure & remove negative battery cable first good luck.

Are you testing the relay when the engine is cold?
The air injection pump works for a very short period of time during initial cold engine start.

Once the exhaust stream is warm enough to support O2 sensor function, the pump shuts off and will not come on again until conditions are met.
Let me know.
Regards,

Your vehicle came with a smog pump. It may have seized up (probably breaking the fan belt) and my have simply been removed by a mechanic at an earlier time. It is located below the alternator on your vehicle.
If there is no pump but a bracket to hold it, it has definitely been removed. Vehicles will often pass a state smog test without the pump. It only works during engine decelleration (when you lift your foot off of the gas pedal)
Charlie

The secondary air injection comes from an electric air pump (replaces the old eng. driven smog pump), it seldom runs, but when the car is 1st started you should hear if for about one minute, kinda sounds like a muffled hair dryer. The most common issue is the hoses get knocked off, 2nd is the electric motor failing.