It finally happened to me. The dreaded P0401 Exhaust Gas Recirculation (EGR) valve was flagging an error. I have owned the 2005 CRD for four months and not had any real problems until now. It has 73,000 miles. I hooked up the scan tool and it indicated that the P0401 error happened four times in one 70 mile trip. I did not get any other errors. From reading this forum, I knew this was not going to be a pleasant experience.

The P0401 error is not specific to the EGR valve itself, however, it is the most likely cause of the problem. I have read on this forum that it could be a stuck open or closed valve. But if the valve was stuck open the idle would be rough or the engine would quit while idling. So my first task was to remove the EGR valve.

I was not able to even see the EGR valve until I removed the battery and moved the fuel filter assembly out of the way. I attempted to access the valve from under the jeep. I could feel it with my hand but could not see it. So I decided to remove the valve by accessing it from the top of the engine. I removed the EGR Pipe by removing the bolts holding it to the EGR valve. No problems yet. Now I needed to remove the four 8mm bolts holding the valve to the intake manifold. This was a mechanical challenge. I could see the two outer bolts and was able to remove them with a 1/4" ratchet. So far so good. The inside bolts I could only feel with my fingers and the one in the rear of the valve I was able to remove with the 1/4" ratchet. It was difficult but doable. The last bolt (inside front) was the problem. It was so close to the block that there was not enough clearance for the ratchet. I could not get access to the bolt with a wrench. After about an hour of fiddling I came up with a way to get to the bolt. I have a set of SAE close clearance sockets. I discovered that a 5/16 socket is close enough to 8mm so I put it on the bolt and used the 8mm wrench to turn it. Finally the bolt was free and I could remove it. Now I am really glad I purchased that close clearance socket set. With all of the bolts removed I was able to move the valve enough to retrieve the metal gasket. I could also get to the electrical connector and remove it. I now could remove the EGR valve and examine it. It took me about three hours to get to this point.

I removed the solenoid from the valve by removing four screws. By looking at the valve it did not look very gunked up. It had a thin coat of black goo everywhere but nothing like the MAP sensor when I cleaned it. The valve was stuck closed. I had to use a lot of pressure to push the valve shaft open with my thumb but after it opened it would move easy until it closed again. I soaked the valve in brake cleaner overnight. In the morning the valve was still sticking as if the brake cleaner had no affect. I read here that Diesel might work so I soaked it in a #2 diesel bath for an hour. I cleaned it the best I could with a Chip brush but the valve was still sticking. I did not want to re-install the valve with this sticking problem. Finally after some thought I remembered the way the old timers would seat valves. They would use a suction cup and spin the valve in it's seat. To replicate this I used a locking Vice Grip to hold the shaft. I spun the valve around while soaking it with diesel. Almost immediately it started to free up. I spun the shaft for about five minutes and the valve was free. I could easily push it in with my fingers and it was smooth and consistent as you pushed it down. The valves (there are two) in the EGR valve re-seated and released the gummy gunk. Now I felt I could successfully replace it. So I re-attached the solenoid and headed to the jeep.

I removed the valve successfully how much trouble could it be to re-install??? Well it turns out that the metal gasket does not want to stay in place when you slide the valve into position. Here is the problem, you can't see the gasket and there is only room for one hand at a time so you can't hold it and the valve at the same time. Finally after several attempts I was able to get a bolt through one hole in the gasket and lightly tighten it. To align the gasket I could feel the ridge of the gasket at the rear of the valve. I used this sense of feel to align it and install the remaining three bolts. The remainder of the installation went without any surprises.

I have been running the "rebuilt EGR valve?" for over a week now and have not had a P0401 code or any code.

The actual EGR valve appears to be built with quality materials. I am surprised how easily it failed? I suspect the oil mist from the Crank Case Ventilation system is mixing with the soot from the hot exhaust gases and is forming an adhesive that is causing the valve to stick. Looks like I need to deal with this next.

The overall project took about 9 hours. So if you plan to do this, make sure you set aside enough time. This is probably not the best project to start with if you are a new mechanic. But look, I saved $200.00 by fixing the old valve. Hope it holds.posting.php?mode=post&f=5#

Would it have been easier if you had removed the flow control valve and intake elbow

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Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

The easiest way is to leave the valve stuck closed and get a GDE Ecotune. No P0401 ever again.

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06 Sport Black 89K leather, 2nd gen fuel, eccotune, ehm, fomoco, steiger window fixes, 7v steel glow plugs, new motor mounts.

Joe, Removing the flow control valve and intake elbow would make it easy to install the metal EGR gasket. This would make room for two hands. However, I am not sure how easy it is to get to the rear two bolts on the elbow. Someone with more experience could provide more information.

obthomas, I have looked at the GDE Ecotune and like what it is. It may be the most economical way to solve this problem if you are sure the valve is stuck closed. Has anyone done an Ecotune with a stuck valve?

I have logged 40,000+ miles with P401 active. I don't even see the engine light any more. EGR stuck closed is worth at least 1-2 mpg.

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2005 sport crd-SOLD No regrets

Very useful information. Thanks for writing it up. I've had the P401 code several times, but it cleared. Probably means that the valve is sticking, but not yet completely stuck. Strangely, my cheap HF code reader was able to show the code, while the readers at O'Reilly and Autozone couldn't.

I use the "Autel MaxiTrip TP100 4-In-1 Auto Computer" to display and clear the codes. It also gives limited engine information and gauges. It works well with the CRD so far. I had no idea that some scan tools would not work with this jeep.

My P0401 code would not occur until it was a hot day (80+), and I was traveling 20 miles or more. Hopefully the EGR is fixed for a while. Repairing one is not a pleasant experience.

After being clear for several months, the CEL lit up with a P0401 code today. Probably a coincidence, but the first time it appeared and today were both both extremely rainy days with standing water on the highways.

Have recently purchased an ecotune. I have a cap welded in the EGR tube which is the same as the EGR valve stuck closed. My EGR valve was stuck closed and I cleaned it before capping the EGR tube. Both instances would set the P0401 code. I had to remove the air control valve butterfly in order for it to run well. After the tune the P0401 code went away and I put my butterfly back in and all works well.

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2006 Liberty CRD 275K, JBA 2.5 with Fox Shocks, GDE Turbo Kit, GDE TCM Tune, Suncoast TC, OEM fuel filter housing converted to fit Caterpillar Fuel Filter 1R-0749, OEM themostat housing modified to accept Hemi 203 F thermostat.

The close clearance socket set you mentioned, are these thin wall sockets? Source?

Wobbly, The close clearance socket set is a craftsman. The sockets look like regular sockets but at the end where the ratchet connects it is shaped like a nut or bolt head. This allows you to put a wrench on the socket to turn it. To use it put the close clearance socket on the bolt you are removing, then turn it with a wrench. These things can get into areas where no other tools can.

Sears calls these 'wrench sockets' : http://www.craftsman.com/shc/s/p_10155_ ... roductPage

An option is this 'socket cap' set:
http://www.sears.com/shc/s/p_10153_1260 ... ockType=G3

i've taken that egr assembly off a couple times, and yea the best ways are either to, remove the battery, battery tray, move aside the fuel filter, take off the fcv and the intake elbow (and the fate hose), or... get under and take of the starter and the oil dip stick and bam! access! (make sure your battery is disconnected or sparks fly!)

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two Liberty CRDs 2005 and 2006