Thread: Air Injection Check Valve replacement

I had an inspection fail on my 06 Grand Prix for 2 codes. po455 and po411. The 455 was an easy fix by changing the evap can in the back. $30 and 10 minutes. The 411, from what I've read, can turn into a nightmare if you don't fix the right thing. I've heard of people changing up to 4 pumps due to water before realizing the check valve was bad allowing the moisture back to the pump. My problem is that I would like to at least check the valve before I go replacing things that may not need it, but am unaware of how to get it off. Older models had a single mounting bolt and then the 2 bolts to the exhaust coupling. I see no mounting bolt, but rather an entire bracket I need to remove?? Any suggestions would be greatly appreciated.

Can't believe how hard it is to find this info. But......I did find some. I have a diagram showing exactly what I need to remove, but I'm not sure yet if I need to rock the engine foirward. Looking at this setup has only verified how ignorant some engineers truly are. Every day at work I see the same inconvenient designs on the machines I run. Designs that create 10 times the amount work than should be for even simple maintenance work. Anyways, if anyone needs this info let me know and I'll gladly share it. Or, if anyone has a suggestion on the best method for rocking the engine, please share. Thanks.

Hey, how did the replacement go? I am in the exact same situation with the exact same error codes and diagnosis. Would you mind sharing that diagram you mentioned? I can't figure out how to remove that stupid thing! Thanks!!!

Bill, the pump on these cars is to the bottom right as you are facing into the engine compartment. Look almost to the front right corner then straight down. The pump is the easier part. The check valve is located to the top back more right than center of the motor as you are facing into the engine compartment. The check valve is a bear to get off as the bolts are covered by the bracket they hold down?!?! Don't know how much help this is in describing. I would post pictures but am not in a position to do so at the moment

Hey guys. Not sure if you still need help, but my little project went pretty smooth. I will try to dig up a diagram and post later in the day, but to make life a lot easier for you when doing this you should remove the air filter duct(between air filter and engine) and then remove the 2 front engine mounts. After the mounts are removed (I just removed the 2 bolts and twisted the mount down out of the way) you can then rock the car ahead(while it's in park) and chock the wheels so it doesn't move. You can now access all the bolts very easily. 2 top bolts for check valve. 2 back bolts thru bracket and check valve. 2 nuts holding flex pipe to exhaust. Then your air line from the pump. It really is quite simple. Again, I will get the diagram posted a little later, I just got home from work and am heading to bed.

Thanks ajohnson! Bill, good to know. I will probably just fix it for now but a delete seems like a good long run solution.... btw, beef jerky rocks! Made some a few weeks ago.... mmmmmm

I must not have saved the diagrams I used, but I did manage to locate one of the pages I found on-line with some diagrams. The 2 bottom pics on the page are the ones to look at. You can see how it all bolts together. Hope this helps guys. how do you replace or repair a secondary air selenoid damper - JustAnswer

That's a nice big easy to see picture. I ordered the part 2 days ago and will let people know how it goes. If I remember and have time I may see about taking pictures of the steps.

Originally Posted by ajohnson2u

Hey guys. Not sure if you still need help, but my little project went pretty smooth. I will try to dig up a diagram and post later in the day, but to make life a lot easier for you when doing this you should remove the air filter duct(between air filter and engine) and then remove the 2 front engine mounts. After the mounts are removed (I just removed the 2 bolts and twisted the mount down out of the way) you can then rock the car ahead(while it's in park) and chock the wheels so it doesn't move. You can now access all the bolts very easily. 2 top bolts for check valve. 2 back bolts thru bracket and check valve. 2 nuts holding flex pipe to exhaust. Then your air line from the pump. It really is quite simple. Again, I will get the diagram posted a little later, I just got home from work and am heading to bed.

I'm in the middle of this project as we speak. Need some help. I can't seem to get access to the bolts and remove the check valve. What do you mean by "rock the car ahead(while it's in park) and chock the wheels so it doesn't move"? I'm at a loss and am having a VERY hard time removing this darn valve due to the way it's bolted in with the bracket. Thanks!

Hi Chris. This seems like a very difficult thing, I know. I was ready to start a search on-line for the engineers who designed this smog control garbage. If you think about it........the vehicles that weigh the most, 8500 pounds or more, big trucks, big tractor trailers, etc.....are the ones that create the most pollution. But guess what.....they are exempt from this. Anyways, enough ranting. To 'rock' the vehicle...you should probably have someone help you at this point. I did it myself, but it's safer with another person. Put your car on a flat surface and put it in park. At the front of your engine are 2 engine mounts that bolt directly to the top of the frame above the radiator. Remove the 2 bolts closest to the front of your car. Now remove the air duct from the air filter box to the engine. Now, with help if you have it, push back slightly on the car to rock the engine ONLY SLIGHTLY backwards enough to push the engine mounts down out of the way. Now, again with help, push the car forward slowly until the engine is as far forward as you can get it and while it is there either you or your help push something behind any of the wheels that will keep it from moving backwards (a rock, piece of chopped firewood, etc..). Now using the diagram and the details I have already posted, you should have no problem getting to the check valve. Just be very careful as you remove things so you don't break other parts on the engine. It's a simple process once you do it. You'll see. Let us know how you make out.