Alright, I need some help here guys and girls. I just installed the P.I. intake, started it up, let it idle for 10 minutes with a/c on and off, etc. Drove it around, was fine for awhile until it threw some codes, P0155 and P0303. First one is an upstream 02 sensor, second one is a cylinder 3 misfire. I fixed the second one by replacing the plug and the spark plug boot, reset the computer by disconnecting the battery again, so all I have now is the P0155, which I don't think is really that important considering I have an o/r h. The problem now is this: at first, the car starts up fine and drives normal, but only after it heats up/has been driven for awhile, it starts to studder and what sounds like misfire under load. It does not seem normal. Here is my question: Is the studdering/misfire under load normal in the beginning for a pi intake swapped car, and does the computer need a long time to re-learn itself? Any and all feedback of people who just did the intake swap, nothing else, would be really appreciated. I would hate to have to tinker with this thing any more.