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2004 Dodge Ram 1500 - Multiple EGR Valve Replacements code P0404

I have replaced the EGR valve 4 times but each time the check engine light comes on again even though I cleared all of the codes. The code shown each time is “P0404 EXHAUST GAS RECIRCULATION CONTROL CIRCUIT RANGE/PERFORMANCE”
I was told that I should have the computer flashed. Maybe I should just disconnect the battery for a minute?

What were the codes that caused you to replace the EGR valve… four times? Post those here so we can advise. Also post the engine size and type in your Ram and how many miles on it.

I think that you have conclusively proven the error codes are not cause by the EGR valve.

Each time my code reader shows the EGR valve is bad. I don’t remember the code number. My truck is a 2004 Dodge Ram 1500 SLT, 5.7 Hemi, 4 door, 4WD. I am also told that some vehicles won’t accept anything but OEM parts so that will be my next move. This last time I replaced it (Saturday) the truck ran better with the bad valve.

Dodge does not make ERG valves , they buy them from a supplier . Also the statement that some vehicles won’t accept anything but OEM parts is nonsense.

I really don’t think there is such a code. So tell us, what was the actual code. There are several that relate to EGR. With the right info you might get a correct diagnosis, and correct treatment plan.

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Well in addition to all the other requests already requested… I should add that the success of your EGR valve operation (as far as your computer is concerned) is not only decided by whether the valve actually opens and closes…it is also dependent upon vacuum (older style EGR’s), power to the electromagnet (newer style EGR’s), the computer control… AND also the EGR pathway which is the EGR tube and or the pathways it uses in order to allow the engine to inhale its own tail pipe emissions. Those pathways need to be open and free flowing with no carbon buildup or blockage. Your EGR valve may actually be working insofar as it opens and closes when asked to do so…but if its pathways are blocked it will report that the EGR is faulty.

Engine codes rarely point to root cause… much more often they point you in the general area to look into not a “be all end all” of what part failed and what the repair is. Think of them more as a suggestion and not a Silver bullet type of thing.

SInce you have more than one of these things floating around… you can leave one of them bolted in place on the engine and hookup another one electrically and vaccum wise to see if it opens and closes at different times as you run the engine. If you notice the valve is actually operating…then your issue will be with the exhaust gas pathways that the EGR valve is trying to connect and disconnect.

This thought process should get you closer to the actual repair.

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The code that keeps coming up is “P0404 EXHAUST GAS RECIRCULATION CONTROL CIRCUIT RANGE/PERFORMANCE”

There’s a problem with the circuit for the EGR valve.

https://www.obd-codes.com/p0404

Not with the EGR valve itself.

Tester

Thank you for that info, that helped a lot!

I appreciate the detailed response! I now have more of an idea how to go about diagnosing the issue.

allpar.com is a site devoted to Chrysler vehicles. Several different forums, as well as lots of background info, are there. You may find help there. I have, several times, for questions about my former and present Plymouth and Chrysler minivans.

Good luck and please keep us informed.

Who told you that the computer needed reflashed?

Some auto parts stores can do this- my Parts Plus can, and it’s less than $100. Not sure if this will help your issue or not, but this doesn’t have to be a dealer only thing.
Disconnecting your battery will not help this issue.

The engine computer monitors the EGR to make sure it is working correctly. The computer commands the EGR to open a precise amount for the particular operating condition, then the computer verifies it actually opens that amount by reading a sensor inside the EGR. I think the problem is that the computer is commanding the EGR to open, but not getting the proper sensor reading that it actually has opened. There’s a half dozen or more reasons why that might happens. Since replacing the EGR ass’y didn’t do the trick, most likely a problem in the wiring between the computer and the EGR ass’y. Could be broken wires, faulty connector, short circuit, or faulty ground. Less likely, the computer could be faulty. A shop would probably start by measuring the voltage of the 5 volt reference to the position sensor. This problem is going to require a proper diagnosis I expect. The replace this replace that method on a guess, while it might eventually work, may cause you to run out of money before you run out of guesses.