hey guys,
just had check engine light come on at 38000. Code says p0406 egr system fault.
im figuring its the egr valve. only problem is if i fix this myself does teh dealer have t0 flash teh system to get the light off or should i be fine if i fix it and do the old disconnect battery trick and try to reset it myself. Also how hard is teh egr fix in these trucks ( i have the 4.7) any help woul dbe great.

 

I can not tell you much about the change out of the part ( I assume that it is a metter of getting to the part, changing it out is a matter of disassemble and reassemble). When starting to take the EGR apart you wanna make sure that there is no carbon build up at the connector point (where the wires run into thevalves top), also when you do remove thevalve itself, make sure that the seat is not all carboned up. If these two possible (though far fetched) issues do not exist than it is probable a bad valve (depending who you are talking to will determine if they consider it a sensor or a valve; technically it is a valve). More times than not this is the reason but remember what the part does, itcontrolsand reducesthe Nitrogen Oxcide emmision (NOx) and the code 0406 is generic for NOx level which is controled by the EGR system, but a bad sensor will trip the code. Before you go tearing things apart you may wanna get a simple emissions test on her. If the NOx level is not registering there than it may be a bad sensor sending false positives to your PCM (the EGR is a valve, not a sensor-again depending on who you are talking to). If it is registering than move forward. Start by scrubbing it up real good or change it out. If not you may need a new emission sensor somewhere in the line, or god forbid an upper engine clean to get rid of some carbon build up (don't worry very rare but mentionable). Once the problem has been solved the code should reset, if it doesnot you can have the codes cleared at a local parts store that has that machine, or not do anyhting and after 40 starts (factory number there) of no repeat code the PCM will clear it. That is what I know, let me know if it works.

 

the dealer wanted $90 just to check the code ( so i went to autozone and had it checked for free) it gave me the code and the possible problems causing it
1.EGR valve
2. Failed EGR position sensor
3. open or short circuit condition
4. failed EGR position sensor
5. failed EGR pressure sensor.

Sucks cause i can do the egr swap no problem, but i would hate to spend the time and money fixing that and then have it be a combination of things. The dealer is such a ripoff so i was hoping to not have to get it fixed there, but if i did i know it should be done right.

 

realitivly new truck, warranty up? I suggested a emissions test because first things first, are you release too much NOx level for the "government" to handle according to your code. IF you are than the EGR is not doing its job. I have never dealt with a Dodge EGR, but I have on a Ford and there is no ****ing with it or bench tests, ya have to replace it. As far as the sensors go, I do not know of any bench tests for emission sensors. The code simply is telling you your NOx level is too high for emissions standard. If you are not releaseing high levels of NOx than we know that the EGR valve is doing its job and it is a sensor thing. As far as the wire cluster is concerned, you would have to find out if it is a closed circuit when closed (shorted) or open (9 out of 10 times it is closed when shorted, like a light switch). Than you test the wires with an ohms meter to find out if there is an open/ short problem. WOW, we are getting way to in this. Find out if your NOx level is truely high or if the EGR is regulating it. That will answer alot. As for my 92 Ford, it was the EGR valve itself.

 

Its the EGR valve. Cost me 55 from the dealer. Its a common faliure. two bolts on the assembly and your done. However you pretty much have to do it blind and you cannot see the bolts your working with. Its located on the driver rear head. It took me an hour and a half to get it on and off.

Just unplug the battery when you do the work and the PCM will reset itself and codes go away since the part is fixed.

 

i read online thatif you have a 06-07 andyou have that code thatit may be a flase code as the pcm has false info. so it said to try and reset the pcm by unplugging the batterysoon my dinner break at work ( i work 2nd shift) i did that left it unplugged for 10 minutes or so then plugged it back in and started her up let her run for afew minutes no light, so i figured maybe i have to drive so i took a quick 20 moinutes drive around town and it never came on. im hoping thats all it was ( i know it is probably not, but maybe) If it comes on again im going to inspect the egr valve see if its stuck and replace it. the dealer wants alot more than $50 for the valve its over $100 at my local dealer. so id rather not spend that $100 and have it be one of the other problems. ill figure it out though. thanks for the information guys.