Secondary air injection system, code P0411

Tiny
PERRI
  • MEMBER
  • 2007 CHEVROLET TRAILBLAZER
  • 4.2L
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 150,000 MILES
I am showing a p0411 code. I changed the fuse, air filter, secondary air check valve and secondary air injection pump and relay. I erased the code. After driving thirty two miles engine light came back on and it is reading code p0411 again.
Sunday, February 18th, 2018 AT 1:29 PM

44 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning.

Do you have a scan tool that can activate the secondary air system?

There are tests that need to be done to find the failure.

Can you here pump run when first started?

Did you clean the passages in the head?

Roy
Was this
answer
helpful?
Yes
No
Monday, February 19th, 2018 AT 2:59 AM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
I only have a regular code reader. Yes I cleaned the passages in the head and yes the pump runs when I start it. Like I said I changed the check valve and installed a new air pump and relay, the only thing I havn't tried is changing the hoses
Was this
answer
helpful?
Yes
No
+2
Monday, February 19th, 2018 AT 2:42 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Ok, make sure there is air blowing into the head. Remove the hose at te check valve and be sure a good volume of air is coming out.

Did you use new or used parts?

Roy
Was this
answer
helpful?
Yes
No
+2
Monday, February 19th, 2018 AT 2:53 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
All new parts.
Was this
answer
helpful?
Yes
No
+1
Monday, February 19th, 2018 AT 3:48 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Okay, the code is for voltage issues. I attached a chart for you to view.

It would help a lot if you had a real scan tool that could read all the live data.

Roy
Was this
answer
helpful?
Yes
No
Monday, February 19th, 2018 AT 3:53 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
Thanks Roy, actually the scan reader I have does read live data. I did go ahead and changed all fuses and relays that pertain to the secondary air system. The only thing I have not changed was the hoses.
Was this
answer
helpful?
Yes
No
-1
Tuesday, February 20th, 2018 AT 2:53 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
I read that before. As I stated before, this is not a component issue it is a voltage issue. You will need to check the voltages at all points to verify voltages and looking for any wiring issues such as damaged or broken connectors and wiring

Roy
Was this
answer
helpful?
Yes
No
+2
Tuesday, February 20th, 2018 AT 3:02 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
Hi Roy,
We emailed each other a couple of weeks ago concerning my 2007 chevy trailblazer throwing a PO411 code. You told me that it is not a component issue. You feel it is a voltage issue. Well I took my trailblazer to three different auto mechanics and they all have checked my voltages and wiring etc. To say the least, all three service centers are completely stumped. Everything checks out fine. They all told me they do not know why it is still throwing the P0411 CODE. From all of their experiences they told me that changing the air filter, the secondary air injection check valve, the secondary air pump, the purge valve, and changing all fuses and relays along with all the voltage and connectors checking out, they find it hard to believe I'm still throwing the P0411 code. Since I spent more than $150 I qualified for an emissions waiver for a year. Do you have any more suggestions? The only other thing I have not changed were the hoses.
Thanks,
ROMANO PERRI
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:28 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Did they check to see if the O2 sensor was changing while they activated the pump?

When the pump is commanded on, all that air goes into the exhaust and it should change the O2 readings until it turns off.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:32 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
I'll have to check with them about the 02 sensors, the one mechanic told me his scanner was reading INC pertaining to the 02 sensor
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:48 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Thats not a reading. Need to see the voltage change

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:50 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
Well one of the mechanics that looked at my trailblazer works for the chevy garage and he told me everything on his scanner said all the readings he was getting was fine so I don't know what to tell you
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:55 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
I understand but he missed something or you would not have this issue.

O2 readings need to be checked with the pump commanded on.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 1:58 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
I'm just going by with what he was telling me, He did show me how he was commanding the pump on and said when he was doing it everything was reading what it should be reading, I was simply taking his word for it since he is a chevy mechanic and Im a construction worker. But yea I agree with you that they are missing something
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:04 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
I agree. A lot of guys test the pump but do not watch the change in the O2 readings to verify the air.

Ask him if he can re check it for you.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:12 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
Thanks Roy, I will do that, what changes exactly should I be lookin for just so I have something to go by when I'm talking to this guy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:20 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Your welcome

It should show lean condition on the O2 sensor

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:23 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
LEAN, got it, in the event it doesn't show lean what would be the solution?
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:25 PM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Either the passage is blocked or the volume of the pump is weak.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:27 PM
Tiny
PERRI
  • MEMBER
  • 11 POSTS
Ok Roy thank you very much, I'll get on it

ROMANO PERRI
Was this
answer
helpful?
Yes
No
Tuesday, March 13th, 2018 AT 2:30 PM

Please login or register to post a reply.

Sponsored links