I have checked my vacuum lines and all is right. I have checked the solenoid and it works. I hear the pump turn on but when it shuts off the CEL comes back on. All hoses related have been checked and are good. Anyone have any ideas on what the problem may be?

 

Have you looked at the actual air pump? Its rare but the pump can overheat and actually burn through causing the vacuum leak. I had a consistant P0411 code that ended up being caused by my ecu. It was damaged and threw that code no matter what I did. Very annoying to diagnose

 

I haven't look at the air pump yet, after reading some I was going to check it out. Thanks for the advice, this code is quite annoying indeed. So your ECU was your cause? How much did that cost you to get fixed or diagnose? If you don't mind me asking.

 

Bought a used ECU on ebay for $50. Honda charged me $75 to program my keys to the new ECU (rip off). I hate the dealer by my house... I had checked and double checked and triple checked hoses. Tried a new air pump, two different relays, took it to Honda and they replaced the air control solenoid (little black sensor mounted on the air box that the hoses connect to) which still did nothing. In the end I'm sure of what happened. The wires that connect to the air control solenoid were frayed when I bought the car. I suppose they tapped the serpentine belt and probably arked off eachother damaging the ECU. Honda charged me $220 to change the air solenoid that nothing was wrong with and then tried to tell me they were going to need to change the air pump and quoted me $1000. Bunch of theives! I spoke with Billman on here and after some deductive reasoning I came to the conclusion the ECU must be damaged. Needless to say I don't do business with that dealership anymore and if I ever have any work to be done I figure it out myself with the kind help of this awesome community