i had that happen to me about 3 months ago, i was flashing code 12 so i bought a new EGR valve for $100 and the light came back on a few days later. I took to my hockey coach who is a mechanic for a honda dealer. He was confised at first but then he remembered a way to test to see if the EGR system is working. What you do is you turn you car on, let it warm up for a couple of minutes then i cant remember if you unplug the sensor on the EGR valve of not. first try it with the sensor pluged in. Then on the driver side of the engine bay under the shock tower just above the power steering reservoir there will be some rubber tubes, one of them says 16 and one of them say 24. disconnect the one that says 16 and you should feel air getting sucked in from it, clog it with your finger and the car should stall. If nothing happens unplug the EGR sensor then clog the hose again and the car should stall. If nothing happens again then there is something wrong with your EGR system and i dont hve any clue how to fix that.
When he did that test on my car, it stalled so the EGR system was fine, but what the reason was that one of the hoses on the right side if the fule injector (there are two of them) the one on the bottom was disconnected. So i put the hose back in and the light never came back on again. So what i'm saying is that check all of you vacuum hoses to see if any are disconected.
When he did that test on my car, it stalled so the EGR system was fine, but what the reason was that one of the hoses on the right side if the fule injector (there are two of them) the one on the bottom was disconnected. So i put the hose back in and the light never came back on again. So what i'm saying is that check all of you vacuum hoses to see if any are disconected.