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OBD-II P0404 Light help

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Old Feb 4, 2006 | 03:17 PM
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Default OBD-II P0404 Light help

99 M6 Z28

was cruising on the highway at 65 mph and my SES light went off. I had the code read and it is throwing the p0404 code. "Exhaust Gas Recirculation Control Circuit" . What does this mean and what do I do to get rid of it. I am in New Jersey and i just bought the car a week ago. I have to get the car inspected in a week or two and need this light off.

Today i took it for an oil change filled it with 93 hess gas and the light briefly went off but came back an hour later cruising same speed on the highway. I was neither accelerating or decelerating.

The car is bone stock it has 52k miles and everything as for filters and basic maintenance seems clean. What do i do and what will it cost me?
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Old Feb 4, 2006 | 03:39 PM
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From: Schiller Park, ILL Member: #317
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P0404 = Exhaust Gas Recirculation Open Position Performance.

Sets when the difference between the desired EGR position and the actual EGR position is more than 20%. That is according to Helms.

Per the manual, it's likely either a bad EGR valve or wiring/connector issue. That means you need to trace the wiring for shorts all the way to the PCM, and check that the connector at the valve is good, and/or you'll need to replace the EGR valve.

Or, the other option would be to remove the EGR system and get tuning to have the codes removed.
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Old Feb 4, 2006 | 06:16 PM
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Thanks a bunch
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Old Feb 5, 2006 | 12:54 PM
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I get the same code. I checked the wiring looking for loose connections and pulled the fuse to the PCM to reset the codes. When I started the engine, the SES came back on. Can I test the EGR itself?
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Old Feb 5, 2006 | 02:07 PM
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From: Schiller Park, ILL Member: #317
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Originally Posted by FSCHW
I get the same code. I checked the wiring looking for loose connections and pulled the fuse to the PCM to reset the codes. When I started the engine, the SES came back on. Can I test the EGR itself?
If the wiring and connectors look fine then chances are you need a new EGR valve. Not sure if there is any way to physically test one, I've had 'em go bad but the pintle on the bottom of the valve still moves up and down freely....
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Old Feb 7, 2006 | 07:24 PM
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Thank you. I am going to take the EGR off tomorrow and see if I can clean it. Do you have any suggestions for a cleaner that is good for carbon?
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Old Feb 7, 2006 | 08:06 PM
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Originally Posted by FSCHW
Thank you. I am going to take the EGR off tomorrow and see if I can clean it. Do you have any suggestions for a cleaner that is good for carbon?
Honestly, I'm not sure what cleaner would be EGR safe, or if a spray type cleaner would even work. Guess you could try carb cleaner, but do so at your own risk; I've never tried to clean one and I have no idea what effect it might have on the internals.

What I can tell you is, if you choose to replace the valve, the GM part number is 17113589 for the valve and 12558353 for the gasket.
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Old Feb 8, 2006 | 08:04 PM
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Took it out today, the pintle was a little stiff. I loosened it up and cleaned it with a little light oil in a Q-Tip. Put it back in the car and the SES light stayed on. I pulled the fuse for the PCM/IGN for a minute or so (I heard that is how to reset the (SES). Still didn't work. I put a voltmeter on the connector and measured 14 volts on pin "E" and 5 volts on pin "D" and nothing on the others, I assume those are signals for the PCM. At this point I guess the next step will be to replace the EGR. Been shopping around the web it looks like they go for about $120.
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Old Feb 8, 2006 | 08:24 PM
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From: Schiller Park, ILL Member: #317
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Originally Posted by FSCHW
Took it out today, the pintle was a little stiff. I loosened it up and cleaned it with a little light oil in a Q-Tip. Put it back in the car and the SES light stayed on. I pulled the fuse for the PCM/IGN for a minute or so (I heard that is how to reset the (SES). Still didn't work. I put a voltmeter on the connector and measured 14 volts on pin "E" and 5 volts on pin "D" and nothing on the others, I assume those are signals for the PCM. At this point I guess the next step will be to replace the EGR. Been shopping around the web it looks like they go for about $120.
I don't think you can repair one of these valves, or at least I've never heard of anyone doing so.

Replacement of a failed valve or removal of the EGR system + tuning are really the only options to get rid of the SES.
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