dude, the red key is for programming the immoblizer, DO NOT USE THE FEWKING RED KEY! it is for the tech to reprogram the unit. Your immoblizer is a type 1 system, similar to the NSX, early prelude, etc.. If you use that red key you will be really screwed. You need to go to the dealership for this one. It's the only way to fix it. What the key does is tell the immobby to gointo program mode. Your immobby still knows the codes to your lost key and will just "tell" your new key the old codes when you get new keys cut. If you put in the "red" key and are not reprogramming and turn the ign on, all codes will be lost. Guess what, you just bought a new immoblizer control unit and reciever. I really hope you didn't try this before my post. I can't believe nobody else knew this.... It should be in your owners manual and the key should have a tag that says dealer use only

 

oh btw, what you others guys are saying is mostly true but this guys car is an older integra and has the older style immobby. The newer style has been upgraded to eliminate the"red key" because of this exact problem. Also it has been upgraded withe newer features such as rolling codes, etc.