I recently installed a AEM ETI air intake into my 2008 is250 and was driving great and sounding really good for the first day but the next day the CEL, Check VSC, and Trac lights all came on. I ran the codes and I got P0455 and P0441. I checked the gas caps as this is a easy quick solution to this sometimes and cleared the codes but they quickly returned and i believe it has to do with the aftermarket intake.
The next day i checked all the wires, sensors and hoses but everything seemed to be fine! If any of you have had similar problems and found the solution please let me know! I can still return the intake but that is my last resort because I really like how it sounds and feels. Thank you!!

 

Disconnect the battery. My Takeda did the same thing. The vacuum hose that connects to the intake was loose due to the slip on connector. I purchased a screw type from autozone and that did the trick. Your issue may be totally unrelated to that but its a good place to start.

 

This did it thank you!! For some reason thats the only hose i didnt think to check...

 

Just keep in mind, everytime you touch the air flow system, you should always reset the ECU to let the car leaning new airflow!!!