I've been getting a P0404 code for the EGR valve intermittently for about the last week. I've pulled the EGR & inspected the piston (checks ok), housing (not loose or broken), gasket & metal ring (checks ok), connection pins (corrosion on middle pin, couldn't access to clean). I cleaned the EGR mounting plate & mounting surface with carberator cleaner, re-installed. Sometimes a P1811 long shift code accompanies it, sometimes not. There seems to be no issue while driving. Maybe a slight miss or hesitation when moving from a start while the engine is cold. I've thought about replacing the EGR, but haven't as of yet. There has been been a slight decrease in mileage from 26/27 to 23/24.
I'm curious if the 1811 follows the 0404, or vice versa? Could a shift kit &/or PCS swap eliminate both, or could swapping the EGR eliminate both?
03 SE P0404 EGR code
- harofreak00
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Re: 03 SE P0404 EGR code
They are completely unrelated problems.
Andrew - owner/operator of Bonnevilles Unlimited

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler

2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
Re: 03 SE P0404 EGR code
Thanks for the input. I'm thinking of changing the EGR outright and then going from there. Even though it appeared to be serviceable, it doesn't mean the valve isn't bad, or going bad.

