Have to get a smog test soon and this code came just in time to stop progress. For me, the problem has always been the passenger side purge valve mounted behind the engine. Such is the case here.
I thought I would try a different method than removing the intake and all the stuff above it, or trying to bathe the purge valve internally with solvent.
Tools/materials needed:
1) 1" deep socket.
2) A couple of long extensions.
3) Socket wrench. I used 3/8".
3) Universal or swivel socket.
4) WD-40
5) High temperature non sealing pipe dope.
6) Medium size flat bladed screw driver to help remove hose clip if present.
7) Valve 22040805.
8) A couple of clean rags.

Steps:
Note: You will be working from the drivers side.
1) Remove brake booster hose from the press on fitting in the back of the booster and pull it out from behind the engine as far as you can. You just want to it out of the way to improve access to the valve you are going to remove.
2) Locate the threaded end of the check valve by hand. There are excellent pictures to visualize what you are doing in this thread:

https://www.corvetteforum.com/forums...eck-valve.html


3) Spray WD-40 on the threaded end of the air valve so that it gets to the threads. You may want to keep one hand on threaded junction while applying WD-40 so you know that
you are hitting the thread interface with the it.
4) Find the hose coupling from the AIR pump and separate the hose.
5) Remove the hose elbow and clip from the driver's side valve.
6) Reach behind the engine to find the hose to valve connection for the passenger side valve your are replacing.
7) You should be able to pull the steel AIR pipe towards you to remove it along with the short hose that fits on the valve. It is best to do this with your hand on the short hose.
Note: In my case, the hose did not have a clip to secure it to the valve. If yours has the clip, you should be able to get a flat bladed screw driver into the clip hole and twist it to release the clip.
8) Put the swivel socket on the back of your 1" deep socket, then put on your long extensions.
9) Grab the 1" socket and push it on to the 1" hex boss of the valve. Arrange your extensions so they exit the back of the engine over the top of the brake booster. This keeps the swivel socket angle low enough
to avoid binding and deliver torque to your 1" socket.
10) Connect your socket wrench and apply torque. The WD-40 should have had enough time by now to loosen up the threads. You should feel the threads finally give to where you can remove the socket and
spin the valve off by hand.
11) Use a rag to clean off the male thread on the pipe behind the engine.
12) Apply a small amount of the pipe dope to the female threads of your new valve and spin it onto the male threaded pipe by hand. This is tapered pipe thread so you should be able to get about 1 turn by hand.
13) Get your 1" socket back on the end of the new valve and tighten it by about 2 turns. You can see how much thread is exposed on the properly tightened driver's valve. By hand you can verify that you
have about the same amount of exposed thread on your new valve.
14) You may want to put the hose clip back on your new valve. I didn't because the old valve worked fine for 3 years without it.
15) Reroute and reconnect all the AIR hoses and metal pipe.
16) Reroute the brake booster hose and coat the connector with some WD-40 before pushing it back into the brake booster.

You are pretty much done. If you have to get a smog test soon, do not reset the codes because you will also reset the IM readiness status which will then take a while to get back. There is a driving cycle you
can go through to clear P1416.
I have average sized hands and fairly thin wrists. I was able to complete this job with only minor scratches. If you have big hands, maybe you can have your son or daughter help you.

Now that I figured out how to do this, I expect it will take about 30 minutes next time. Putting some pipe dope on threads and leaving off the hose clip will help a lot.



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Would be afraid of twisting and damaging the steel line without using a back up wrench. Don't think WD40 would loosen threads to make any difference. Probably yours has been off before and not that tight maybe. Still might be worth a try just dont put much torque before stopping.

 

I also had that concern about bending the pipe. First time I tried to turn the wrench it wouldn't budge. But the good news is that the pipe/valve assembly did not flex when I applied high torque. Then I applied the WD-40 and let it sit for 10 minutes. After that I had no problem breaking the valve free. The thread lube I put on this time will make it easier next time.

You are correct that the valve has been replaced before; about 6 times on this car.

The end of the pipe is welded to a bracket which is bolted to the engine, this provides a high degree of backing for the applied torque. But it is not as good as having
additional back-up with a second wrench too.

Cheers

 

Have you considered relocating the valve for easier replacement? The last time mine "failed" that was the route I took. Since doing that, back in December, it passed a CA smog test where the Smog Test technician appeared to do a thorough visual inspection.
Here's my writeup on the relocation: https://www.corvetteforum.com/forums...post1603858478

 

Hi Metalman I saw you writeup after I put mine in. Wish I'd seen it before because we are on the same page. One thing I could not determine is where you finally mounted the passenger side valve.

I was very keen on relocating, but replacing the valve is pretty easy the way I did it so for now I'll just replace them every couple of years. Someone said in another thread that the passenger side valve gets cooked more than the drivers side because of its warm location behind the cylinder head. That would be a plus for relocation; you probably will never need to replace it again!!

As I said the concern about breaking the pipe with the method I used is valid. But WD-40 loosened it up quite a bit, the pipe is backed up somewhat against torque flexing by the bracket, and I used a short handled
3/8 ratchet to limit the torque I could apply. The first time without WD40, I hit a brick wall- nothing moved or flexed so that is good news.

Off to the smog station once that CEL turns off.

 

Good luck on the smog test! And hopefully this valve will last you a while.

That's weird, maybe it was somewhere else that I shared these pictures:

 

That's a good location!!! What sort of compression fitting did you use to get onto the pipe? I know Swagelock has some that are rated for about 1000F

 

It's this one from Amazon: 304 stainless steel, they rate it up to 660 F which should be plenty high enough. If it sees higher temps than that then there will probably be bigger problems!

 

After replacing the valve the check engine light went out after 4 drive cycles and P1416 only showed up as a history code. I thought I was good to go on the smog test. My TECH2 showed that all the IM readiness were complete, but still showed a pending P1416.
I failed the test because the code was still pending. I didn't want to clear the code because clearing also resets the IM status to not ready. The good news is that the factory service manual has a great description of how you can get each individual
IM status to change to complete. After clearing the code, it only took 15 miles of driving from a cold start. See pages 6-905 to 6-920 of the manual. The general procedure you see on the web is not correct. To get the catalyst IM to complete, the manual says you should cruise for 5 minutes at 55, coast down to 0 (which is impossible), and then idle for 2 minutes. I did this twice to get the catalyst IM to complete, but I coasted down about 4 mph (idle in 4th gear). It helps a lot to monitor the IM status as you go through each set procedure.
Finally passed smog!

I should have tried to just run the set procedure of the the AIR IM status. This procedure requires 2 minutes of idle with the engine already warmed up, then after getting into closed-loop fuel control you accelerate to 45 mph, cruise for about
3 minutes while waiting for the AIR system status to update to yes. Next time maybe, but where do I find a place to cruise for 3 minutes at 45 mph without stopping or getting run over?