I tried to remove the engine air filter , by releasing the 4 clips (2 on each side). However i am unable to open the box. It appears that the lid its stuck at one corner (the outside , closest to the firewall).The plastic box is raised there, but i dont see anything that could be moved or pushed.

 

I am having same problem. Do you just force it? I don't want to break anything.

 

its a very tight fit, try pulling to the left as you pull it off

 

Thanks! That works but the "left" was the front of the car for me.