brajgreg

All,

I have a 2007 JK Unlimited Sahara, and a few months back I got the P0406 code. I came here, followed the instructions on how to replace it since the vehicle has about 95k miles on it (and has had a lot of rust issues), and the code went away. The old valve looked pretty cruddy. Well, it's been a couple months, and now I'm getting the trouble code again. What would you recommend doing now? I've seen people talk about wiring issues or shorts or connector issues, but I can't seem to find any information (or threads/posts) on how to troubleshoot any of those other issues. I can't even find a good diagram of where the other end of the cable goes to that doesn't attach to the EGR valve so I can try to check and see if it's damaged. So if anyone has any information on things they tried to fix the P0406 problem AFTER replacing the valve, I'd very much appreciate it.

karls10jk

I replaced mine and the code came back a month later. I replaced my freshly replaced valve under warranty and have been code-free for a while. Not that my case is the rule or the exception, but it's possible.

zstairlessone

They can and do fail at any time with little or tons of hours on them.

RoubsX2

I wanted to add to johnjutsu's great idea that one of these half moon / obstacle wrenches should also make quick work of the hidden bolt from the same underneath angle.

steelzeppelin

I have an auto. Removed the fender, tire, trans tube bolt, and un bolted wiring along the frame(used frame for leverage). I used ratchet straps to pull the trans tube over and used a 10mm gearwrench to get the "hidden bolt" off. I did hook a double box end wrench to the open end of the gear wrench and put a drive extension through the other end of the box wrench as a member suggested. This was a lifesaver! I couldn't have done this project without you guys. Great write up and great suggestions on the thread Thanks again!

Total time
20 mins on fender and tire removal
20 mins on trans tube bolt, first three bolts, and other misc work.
4 hours on hidden bolt (use wd40 or liquid wrench)
This was an overall terrible experience

Snake Doc

Great write-up. I had a different experience with changing my EGR Valve. I have a 6 sp manual and was able to complete the change in less than an hour. Took of the inner fender for easier access. Used a small slim socket for the back hidden bolt and also removed the front bolt. CEL light is off. Hopefully I will not have the same issues with the CEL light and a new EGR valve was the fix. Again thanks for the write-up!

jnelson214

First off, Thank you for all of the input on this, saved me a solid $400-$450. I did mine on friday night and total time was just over 1 1/2 hours of work time.

Took off tire, removed the wheel well, sprayed a whole lot of PB Blaster on the 4 bolts, hidden bolt rubbed with my fingers and towel. Waited 30-40 minutes and went to town. I had no issues with the 3 bolts and with the hidden one I tried the flex wrench 10mm but couldn't get enough grip on it so i used a box wrench with offset to allow me to grip the bolt and pull the wrench. It worked for me to loosen it then finished with ratcheting flex wrench. Pain in the butt but well worth it.

Thanks again,