If your 07-11 JK Check Engine Light (CEL) has been coming on intermittently or is on at all times while the engine is running, you may have a bad Exhaust Gas Recirculation (EGR) Valve. Three possible diagnostic trouble codes (DTC) can be set in the Powertrain Control Module (PCM) if the EGR valve is bad. The specific codes are P0404, P0405 and, P0406. You will need code reader to plug into the OBD-II connector under the drivers side dash panel.
In my case, my 2009 JK has had the CEL coming on intermittently for about two years. Since I have a Supechips programmer, I was able to determine the code (P0404) was indeed related to a degraded EGR valve sensor performance.
While replacing an EGR valve is a relatively easy job, the fact that it is located in a very tight location on the JK will make it very difficult to replace. Consider yourself forewarned!
The EGR valve on a JK is located on the back of the passenger side cylinder head between the engine and the firewall.
What you will need:
The first thing you will need to do is disconnect the battery. This will clear the code and reset the EGR learn cycle from the PCM. Failure to clear the EGR learn cycle could trigger the CEL after you install the new valve.
The easiest way to get to the EGR valve is to remove the right front tire and RF inner fender liner.
What you will see with the fender liner removed.
Now would be a good time to spray penetrant on the four bolts. Remove #6 plug wire from the spark plug to gain a little more access to the valve.
Remove the two 8mm bolts holding the tube to the valve. Note: Be careful not to bend the tube!
With your 10mm gear wrench, loosen the lower 10mm bolt holding the valve to the cylinder head. This bolt will be extremely tight. Make sure your gear wrench is on the bolt all the way to prevent rounding off the head of the bolt! Do not remove completely.
Now the fun part…If you have an automatic transmission, you will need to slightly bent the dip stick tube towards the firewall to gain better access the top EGR valve bolt. Use a small pry bar between the valve and tube and bend back slightly. Chances are the tube will spring back to its original position so just work it a bit until you have better access to the bolt. This bolt is also very tight and to loosen it, you may need to double up two wrenches. What really sucks is as you loosen the bolt it will push up against the tube. With your 10mm gear wrench loosen the top bolt until it is completely unscrewed from the cylinder head leaving the bolt and wrench somewhat pinched in place. Now, with your second 10mm wrench or by hand, remove the lower bolt completely.
You should now be able to push the valve and wrench back towards the firewall and down slightly to gain access to the five-pin connector on top of the valve.
To remove the connector, you will need to slide the red lock clip back towards the firewall with your pick. The connector is very similar to the connector on your hard doors wiring harness. Once the red lock clip is pushed back (about 1/8”) you should be able to squeeze the top of the connector-locking tang and remove the connector. This will prove to be easier said than done.
After you unplug the connector, you can remove the EGR valve.
Install the new EGR valve in the reverse order starting with installing the two new 10mm bolts on the valve with the new metal gasket. Put a little anti-seize on the bolt threads. Now, work the valve into position, connect the electrical connector, and push in the lock pin.
With the valve in position, start threading in the lower 10mm bolt by hand. (Do not tighten) Be very careful not to cross thread the bolt! It should go in somewhat easy. Then, very carefully start threading in the top bolt with your gear wrench. Snug up both 10mm bolts to acquire an even seal. Do not over tighten.
Install the EGR tube with the new gasket and 8mm bolts. Do not forget to add a little anti-seize to the threads. These bolts do not need to be super tight; just snug!
Re-install the plug wire, connect the battery and, install all the other bits you removed.
I hope this helps anyone feeling adventurous repairing their own Jeep JK.
In my case, my 2009 JK has had the CEL coming on intermittently for about two years. Since I have a Supechips programmer, I was able to determine the code (P0404) was indeed related to a degraded EGR valve sensor performance.
While replacing an EGR valve is a relatively easy job, the fact that it is located in a very tight location on the JK will make it very difficult to replace. Consider yourself forewarned!
The EGR valve on a JK is located on the back of the passenger side cylinder head between the engine and the firewall.
What you will need:
- Replacement EGR valve. I chose the Dorman OE Solutions from O’Reilly Part# 911-242. It comes with two required gaskets and 4 new bolts.
- ¼” ratchet with a 4” Extension and 8mm socket.
- 10mm gear wrench and a regular 10mm open and box end wrench.
- 1 small mechanics pick.
The first thing you will need to do is disconnect the battery. This will clear the code and reset the EGR learn cycle from the PCM. Failure to clear the EGR learn cycle could trigger the CEL after you install the new valve.
The easiest way to get to the EGR valve is to remove the right front tire and RF inner fender liner.
What you will see with the fender liner removed.
Now would be a good time to spray penetrant on the four bolts. Remove #6 plug wire from the spark plug to gain a little more access to the valve.
Remove the two 8mm bolts holding the tube to the valve. Note: Be careful not to bend the tube!
With your 10mm gear wrench, loosen the lower 10mm bolt holding the valve to the cylinder head. This bolt will be extremely tight. Make sure your gear wrench is on the bolt all the way to prevent rounding off the head of the bolt! Do not remove completely.
Now the fun part…If you have an automatic transmission, you will need to slightly bent the dip stick tube towards the firewall to gain better access the top EGR valve bolt. Use a small pry bar between the valve and tube and bend back slightly. Chances are the tube will spring back to its original position so just work it a bit until you have better access to the bolt. This bolt is also very tight and to loosen it, you may need to double up two wrenches. What really sucks is as you loosen the bolt it will push up against the tube. With your 10mm gear wrench loosen the top bolt until it is completely unscrewed from the cylinder head leaving the bolt and wrench somewhat pinched in place. Now, with your second 10mm wrench or by hand, remove the lower bolt completely.
You should now be able to push the valve and wrench back towards the firewall and down slightly to gain access to the five-pin connector on top of the valve.
To remove the connector, you will need to slide the red lock clip back towards the firewall with your pick. The connector is very similar to the connector on your hard doors wiring harness. Once the red lock clip is pushed back (about 1/8”) you should be able to squeeze the top of the connector-locking tang and remove the connector. This will prove to be easier said than done.
After you unplug the connector, you can remove the EGR valve.
Install the new EGR valve in the reverse order starting with installing the two new 10mm bolts on the valve with the new metal gasket. Put a little anti-seize on the bolt threads. Now, work the valve into position, connect the electrical connector, and push in the lock pin.
With the valve in position, start threading in the lower 10mm bolt by hand. (Do not tighten) Be very careful not to cross thread the bolt! It should go in somewhat easy. Then, very carefully start threading in the top bolt with your gear wrench. Snug up both 10mm bolts to acquire an even seal. Do not over tighten.
Install the EGR tube with the new gasket and 8mm bolts. Do not forget to add a little anti-seize to the threads. These bolts do not need to be super tight; just snug!
Re-install the plug wire, connect the battery and, install all the other bits you removed.
I hope this helps anyone feeling adventurous repairing their own Jeep JK.
